http://www.chickenhead.com (no, I’m unaffiliated)
I never had a better laugh than when I found this site.
Keep me rivited for some time. http://jumptheshark.com/
SuperGreg is a web site setup by the Lee Dungarees Corporation. It is a brilliant fake amateur web site. Super Greg is a paid actor who appeared in commercials with that Buddy Lee character.
Haj
I would second the nomination of the Bert-Osama Bin Laden poster and all the news stories it spawned.
Thanks to 123 at Cafe Dartre.
http://www.stupid.com/games/index.htm
“Warp Bill’s Face” is nearly as funny as the “John West Bear Fight”.
Not appropriate to link to, but several times I received a file called “horse gag.avi”
For reasons of tact, I will not describe it here, but the version with sound is 100 times funnier.
Can you belive he’s divorced?
If you like the Cookbooks from the 50’s - visit
http://www.lileks.com/institute/gallery/index.html
or its parent site:
http://www.lileks.com/institute/index.html
Can you belive he’s divorced?
Aw come on das…leave Peter alone. Personally I love this guy. And he won the Webby and came in full Pan regalia. It just fun to see a guy who is a kid at heart.
Plus he recently found his Tinkerbell. Hooray for Peter!
Shakes: I almost peed myself reading the chili contest.
The funniest thing I ever read was the “Goat Cannon” thread on SDMB. Absolutely cracked me up.
Of course, you can’t go wrong with the classics.
I still haven’t seen anything that had me on the floor quite as quickly as I’m A Cow. It’s MacroMedia Flash, and takes about a minute to load on my dialup, but it’s worth the wait. Patience has its rewards!
Um…it should be noted that the animation is not suitable for minors, really…
jayjay
I find this audio quite amusing.
Warning: contains multiple uses of the Fword.
Two of my personal favorites:
Can you tell I like cats? Okay maybe not from actually reading those but if you’ve ever had to bathe your cat or give them a pill, you know those are only slight exaggerations. 
The Monkey Butler Thread cracks me up every time I dig it up and reread it. I don’t really know why.
Waterj2: Whatever happened to Homer? Why don’t you try and get him back?
I have never been completely sure whether laughing too hard at this website is the correct response or not. In fact, it makes me feel a little ashamed. What do you think?:
If you haven’t seen this yet, go here now:
http://www.threebrain.com/weeeeee.html
Some people like it, some don’t. I loved it.
I guess that you just have to have the right sense of humor for it.
(Tell me what you think)