Seriously rotted milk. Not just gone over, but someone leaves a glass of milk downstairs in the family room and forgets ( this would be a son-type of someone 
) and then we go away. For a week. In the summertime.
We came home and assumed all four cats were dead and bloated. When they scampered in to greet us, we started thinking an animal had gotten in. Oh man. What a horrible scent.
It beats necrotic flesh hands down. ( pardon the pun )
Cartooniverse
I can’t speak for other cases, but this particular girl isn’t very bright.
I’ve been wondering about that…
I guess I’ll join the putrified seafood line of experiences, and like pulykamell pointed out, surstrømming is one hell of a candidate for bad smelling marine products. But on the other hand they’re not too bad to eat though (cough), actually, you need a lot of raw red onion with it though.
As for my own experiences
when as a kid poking around on the seashore, we found a mysterious wooden barrel wedged in between some rocks. Curious as kids are, we found some rocks and started banging on the lid, until it finally cracked, and the smell literally blew us backwards. It was full of rotting herring. And before we even could find our bearings after the smell had whaked us around, the sound of hundreds of eager seagulls came pouring down on us, and we managed to crawl to a safe distance only to see the barrel explode like a miniature atomic pouf of white feathers and gleeful seabird sounds. The smell? For us; almost like a concussion. For the seagulls; probably orgasmic.
later when the seashore poking kid had turned seashorepoking into a profession, there were some seal studying colleagues doing a project on the stomach contents in bearded seals. To do this they about a dozen bearded seals in one of the labs (dead of course). For the rest of us, coming in the front door of the facilities produced a hint of something not right, walking in to the microscopy lab next, gave a stronger hint of something really demonic, but walking in to the hallway leading down to the aforementioned lab with bearded seal stomach investigations, made you walk in slow motion, the stink was too thick to walk through. And if you managed to the lab, you would faint, but not fall down, because the stink was so bad it held you up. The stomach investigating colleagues would then just open the back door and let the stink carry you out into the parking lot where it would dump you sprawling on a snowmobile and you would wake up gasping for air and not remembering how you ended up in the parking lot. I still have alot of memorygaps from those days. Strange.
working with other seashorepoking professionals also produce the strangest stories. One of these colleagues told of his father who one day had found a dead whale stranded on the beach. This shorepoking father having not outgrown the childlike curiosities had to fetch something long with a blade attached to the end of it, and started poking the whale with it. The result was devestating. The whale erupted like a volcano and the poor soul was standing in the horizontal stream of a fountain of whaleguts. I guess the smell must have been overwhelming, but the sensation of being drowned in rotting whaleguts must have been a tad bit more shocking in that instant.
Suddenly I’m not hungry anymore.
Oddly enough, I now have a craving for seafood.
You mean my escapades in general, or this one in particular? Assuming you meant this one, that’s pretty much it. We found a booking slip from the Austin jail which showed he had been busted for public intoxication the preceding Saturday night. He apparently paid the fine, went home and washed down a handful of Thorazine with some booze, which is never a good idea.
We found him lying half in the bathroom, half in the hall. He had been wearing underwear only and had decomposed in the heat so badly that he had pretty much popped in more than one place. Hence my comment about him being all over the walls, etc.
Although I turned pretty green, I managed not to barf, which gained me brownie points as I was still considered a rookie. The ambulance guys that had to pick (scrape) him up did not fare so well. My partner had been around for a while and he showed me the coffee trick, which thankfully I’ve never had to use since then.
A skunk that was hit by a car right outside my house, the tar paving right outside my house on an 90 degree April day, and a house with a 5 day old corpse inside it were all bad, but the smell that wafted over New Jersey on September 12 & 13, 2001 was the worst because of the source.
Okay, I see a couple of other requests for stories, so I will tell one on myself. It’s been 30+ years since this happened and I still think it’s one of the funniest things that has ever happened to me. For those familiar with the Austin, TX area, you’ll recognize some of the descriptions.
I started out in the Communications Division and worked my way into Patrol. My very first night out on the street as a commissioned peace officer, my partner (let’s call him Bill) and I had taken a burglary call in Del Valle, which is just east of Austin and at that time was the location of Bergstrom AFB (now the Austin airport). We were parked in a parking lot at about 0230 while I wrote the report and Bill snoozed, in the time-honored manner of officer training everywhere. As we are so occupied, a car comes sailing past us doing just under the speed of sound. I dropped the clipboard, threw the car in gear, stomped the gas and hit the lights and siren, promptly scaring Bill back awake. I go sailing after the speeder and finally pull them over up by the Bastrop interchange on 71.
We get out, and as the driver, I make the contact. Bill gets out and checks the back seat of the car for a midget with a bazooka, doesn’t see anything and moves around the front of the car. In the meantime, the driver has exited the car and she is one of the most stunningly beautiful young women I have ever laid eyes on. I hit her up for her license and start in on the routine about why was she speeding, was there an emergency of some kind.
Her: Yes, sort of.
Me : Sort of?
Her: Yes, sir. I just started my period and I’m trying to find a gas station with a restroom so I can put in a Tampax.
Now, as Bill tells it, my lower jaw hit my kneecaps and I stood there for a moment. I’m still trying to be Mr. Professional Deputy and all that, so the conversation finally continues.
Me : Ma’am. that’s not a real emergency.
Her: Well, it is to me!
I start writing the ticket.
Her: Are you going to give me a ticket on top of all this?
Me : Yes, ma’am.
She does that thing that women do where they manage to inflate themselves up to about three times their regular size, gives me The Look and unloads on me.
Her: YOU COLD-HEARTED LITTLE BASTARD! THE LAST FOUR COPS I TOLD THAT TO LET ME GO!
Bill cracks up laughing. After a moment, so do I. After a moment, so does she when she realizes that she just stuck her foot in her mouth. I was nice and only wrote her for 70 in a 55 (I’d clocked her at 95) because she had amused me.
The next day, I come into work. Bill has told this story all over the department and on my locker is a freshly drawn sign:
THE COLD-HEARTED BASTARD
OF TRAVIS COUNTY, TEXAS
Ginko Nuts. Seriously.
Country song! Country song! Someone write that, it’s a country song!
*Public bathrooms I’d encountered in India. Jeezus Gawd!
*The stinkles (wrinkles + stink= Stinkles) on my Pugs face. Cleaning that out with a Qtip is enough to make a vomitorium attendant gag.
One of the worst odors I’ve encountered? That would have to be the time DH and I visited some friends who lived in a (small) trailer in Mississippi. They had an Australian Shepherd bitch who had come into season shortly before our visit. Because they only allowed her to mate with another Shepherd, they had her shut up.
Now keep in mind that this was a SMALL trailer–not these new, nearly-luxury models you can get nowadays. This was one of those where you’ll bump your shoulders on the walls when you walk down the hall. The bathroom was so small that your knees nearly brushed the bathtub when you sat on the toilet. It wasn’t till I had to “go” and walked into that bathroom that I realized that that was where they’d quarantined the dog for the duration of her heat. No windows or any ventilation–just a dog in heat in an airless, postage-stamp-sized bathroom.
Pee–YEW!! Every hair in my nose started to smoke. My olfactory nerves begged for mercy, but I could not grant it, because I really had to go, and there was nowhere else to do it. I had to breathe as shallowly as possible through my mouth–although I had to squelch a minor rebellion on the part of my lips, which tried to lock themselves shut in self-defense. Needless to say, I finished my business in record time, sparing only a few seconds to rapidly wash my hands and flee the scene!
It’s not the worst odor, but this one is noticeable. I had an organic chem lab in which we synthesized and crystallized Ferrocene, an organometallic compound. The purest samples come from subliming this, heating the raw mateerial and condensing the crystals from vapor on a chilled surface. You get a good whiff of the vapor when you lift the lid to scrape off crystals. It’s got a notable sour-milk odor to it, which I notice the Wikipedia page doesn’t mention:
Ah, God, I didn’t think of that. 
I wonder if Germans living near Auschwitz noticed the same thing.
I had a summer job in the maintenence department of a hospital once. I ran the medical waste incinerator. I can’t pick out one single incident that was the worst, but big bags of biohazard in the Tennessee sun produced the awfulest smells I have ever encountered in my life.
So when you were deciding what you wanted to do for a living before going to college… were things like that in the campus job flier?? LOL
“gee what do I want to do for the rest of my life?”
“You get to do and smell WHAT??”
“YES! THATS IT!! Thats what I want to do!!”
3rd worst: Rotten, decomposed white rice from a Tupperware bowl at the back of the fridge.
2nd worst: Grossly obese woman at the laundramat. I think she probably had that thing going on where the bacteria grows in the folds of flab that never get washed coupled with being too fat to attend to other basic hygene practices.
1st worst: I have a python and a boa. I usually feed them live rats but several years ago I was buying frozen whole rats. I was going to school at the time and working full time so I was usually in a hurry. One night after I got home from school I wanted to get the snakes fed but had forgotten to take the frozen rats out of the freezer. I took the bag with the rats down to the basement, put them on a piece of sheet metal and positioned an infrared heat lamp over them. Went upstairs, watched a little TV, went down to check on the rats, DAMN-still frozen solid! So I moved the lamp closer and went back upstairs for a bit. Fell asleep and awoke a half hour or so later to an indescribable oder. Ran downstairs and the rats had not burned but had cooked to the point that they had burst. Split right up the middle of the belly and spewed rat guts filled with rat crap baking under a heat lamp. It was really bad. Really. Thankfully the basement aired out fairly quickly once I opened the windows (mid winter) with no lingering smell.
I think the stinkiest odor I have ever encountered was the dead cow, rotting in the summer heat, in a stagnant pond, in my advanced field geology class field area. O Boy that was **RIPE **::blech:: makes me gag to think about it.
Sorry to bump thread, but I have to respond when a guy with over 3,000 posts quotes my entire fricking anecdote.
No. I went to become a Family Doctor full of love and joy. I fell in love with surgery and did a couple of years of it. (They said to me when I was well and truly stuck in it, “This program builds character. Just look at the characters it’s built!” Yeah.) I did some surgical research, which didn’t go well, switched to pathology, and was bored. My fifth month, they sent me down to Forensics.
The first thing I saw was a guy sleeping in his clothes and tennis shoes on a gurney in the hallway outside Forensics. I went up to him and said, “Sir, you can’t sleep here.” Then I realized, uh, he wasn’t sleeping. And that he did have an appointment to see a doctor.
To be seen by a doctor.
He wasn’t gonna see a doctor ever again.
I had a great time in Forensics and realized I’d found my vocation. The amazing smells just sort of came along with the ride.
This cooler filled with rancid tacos I found in the woods.
Gangrene.
When the 300+ pound guy rolled into the department on his scooter for a foot x-ray. Another tech and a doc from the ER unwrapped his foot.
His leg from the knee down resembled what I imagine burnt dinosaur flesh would look like: lumpy, bumpy, black, and crusty–but with a cream filling underneath.
His foot, though, mainly consisted of slime.
The smell was too foul to describe. Oh, fuck, ick. I hate thinking about it.
When the lateral tib/fib picture displayed on the monitor, I asked the doc, “Where do you think it’s coming off?”
The doc pointed to a point just below the knee and said, “Right about there.”
I’m gonna take an extra long shower now.