I’ve been burning with lust for at least forty years and it hasn’t done me any harm.
Seriously, though, at least twice in my youth I was callous and insensitive to women who clearly loved me, even though (at the time) I didn’t deserve it. It is not a wild exaggeration to say that I’ve spent the rest of my life trying to make up for that failing.
I feed trolls.
When I was 5, I used to take random small objects from our garage like nails and screws and spare fuse-box fuses and drop them into the gas tank of the neighbor’s car next door. I think that I found the clunk clunk splash sound amusing. But I’d always put the gas cap back on afterwards.
Also, after dinner in the summertime, when the windows were open, I had a habit of whispering their dog’s name. A round of “Dammit Dog! Quit Barking!” would usually ensue.
The service is slow and the pizza is never worth it.
I once deliberately did not return my tray to the full upright and locked position prior to landing.
+1 Hehehe
Good pull on the reference there, chunk. 
I had an affair.
When I was about 13 I sort-of molested an 11-year-old relative.
Family dinner, we were all at the table, and for shits & giggles I put my hand on her knee. She didn’t stop me. I started rubbing. She didn’t stop me. I moved my hand “north” a little bit, continuing the rubbing motion. She didn’t stop me. I continued this until I got within half an inch or so of the goal line [so to speak], before a little angel appeared on my shoulder and told me to cut it out.
We never spoke of it again.
Criminally: I stole a pack of baseball cards from a K-Mart.
Non-criminally: In middle school, I made fun of a boy with a physical deformity, right to his face. I still regret that.
I invented a time machine in my youth and went back and decided to manipulate events so a random dude in Austria could become chancellor. Well, let’s just say it worked a little too-well and now we’re all stuck in this suck-ass timeline.
Did you atone for it by doing the truffle shuffle?
I once entered a pie eating contest. But before it started I drank a whole bottle of castor oil and swallowed a raw egg. When I was on my fifth pie I began to imagine that I wasn’t eating pies, I pretended I was eating cowflops and rat guts in blueberry-sauce.
Slowly a sound started to build in my stomach. A strange and scary sound like a log-truck coming at you at a hundred miles an hour. Suddenly, I opened my mouth. And before Bill Travis knew it, he was covered with five pies worth of used blueberries. The women in the audience screamed. Bossman Bob Cormier take one look at Bill Travis and barfed on Principal Wiggins. Principal Wiggins barfed on the lumberjack that was sitting next to him. Mayor Grundy barfed on his wife’s tits. But when the smell hit the crowd, that’s when my plan really started to work. Girlfriends barfed on boyfriends. Kids barfed on their parents. A fat lady barfed in her purse. The Donnelly-twins barfed on each other. And the women’s auxiliary barfed all over the Benevolent Order of Antelopes. And I just sat back and enjoyed what I created. A complete and total Barf-A-Rama.
Mostly when I was young:
-in spite of suffering some horrendous bullying during elementary and middle school, I was actually bullying another kid at one point in middle school. A teacher who knew my history of being bullied caught me in the act, and (among other things) calmly said to me, “you know, there are a lot of people who think you aren’t like that.” I saw the hypocrisy of what I was doing and felt pretty bad about it; never did it again.
I killed some small animals with a BB gun.
I stole from my employer. Got caught, forced to pay it back. They didn’t prosecute, and in a further act of mercy, they gave me an opportunity to quit, rather than firing me; that way whenever a future job application asked “have you ever been fired from a job,” I could truthfully answer no.
Vandalism. Smashed a couple of garden gnomes, took out a streetlight or two with a well-thrown rock.
Once while backpacking with my family in Yosemite I saw a deerfly land on my mom’s hand. She didn’t notice it, and although I knew it was going to bite her, I didn’t say anything. Yup, after a second or two it gave her a painful bite. I immediately felt bad for not warning her, and to this day I still don’t know why I didn’t say a goddam thing.
Now that I’m 40, it’s hard to believe I ever had a mindset that could have done all that stuff.
When I was a kid and it was my turn to wash the dishes - I found the cutlery particularly tedious and boring. I discovered the dinner knives would slip down the drain with no effort on my part.
Fast forward 20 years and I inherited the family home. The first night I moved in kitchen sink wouldn’t drain, so I called a plumber. He pulled 8 rusty knives out of the space between the sink and the trap. I deserved that.
That certainly wasn’t the worst thing I’ve ever done - but I’m not sure I want to bare all at the moment.
This phrase will be stuck in head for awhile. 
Not only do I not wish to share the worst things I’ve done for fear of irreparably damaging my pristine reputation on this board, I’m frankly a bit angry that you led me to think about them again.
This not-so-spotless mind longs for a little eternal sunshine.
Twice in my life, I’ve been in relationships with women who clearly wanted to get married, and I pretty much knew that that wasn’t in the cards, but I stayed in the relationships anyway… basically, wasting a bunch of their time.
Wasted time at work on SDMB.
OH, yeah, almost forgot…killed a girl in high school using only witchcraft.
Truthfully, though, the worst thing I’ve ever done was hitting a small dog by accident, and not stopping. It ran out in front of me, and I tried to stop for it, I felt it under my tires. I was in a hurry, so I just went on my merry way.
During my sophomore year in high school I was dating this girl (“Joanne”) who went to another school. Through hanging out with her I got to know her circle of friends including this other girl, a junior, who was sort of her rival (“Paige”). My GF complained about her a lot. Anyway, one day Paige gave me a ride home, since she was the only one who had a driver’s license - not too mention a Mustang. She and I started hanging out on the sly.
One day Joanne called me at home and my brother answered. She asked if I was home and he said, “No, he’s on a date with Paige.” :smack:
That ended… ugly.
Qin, I can think of at least four things I did in my twenties that merited a serious physical beating, but I’m not going to list them here. That would be stupid. I don’t think anyone is going to be more forthcoming.
Avoiding my responsibility for child support in my early twenties was pretty bad. It wasn’t quite curbstomp worthy, but it was certainly open-handed-slap-across-the-mouth worthy.
But, Joanne, honey! I only did it for her car!