Not from youtube but still amusing:
Make You My Bitch - Flash Animation
Might not want to watch this one until you see Ironman:
this one is hilarious and the girl is smokin hot!
Sexual Innuendo Music Video (Pakwit - In Slow-Mo)
Time to do a little thread Necromancy with this hilarious number about premature ejaculation:
Edited: Might have to manually copy paste the url in the reason editing spot if it’s not working. Forum software’s auto Youtube URL implementation has can cause an otherwise viewable video to not be viewable.
HAHAHA that made me laugh out loud
lol some of these clips i have seen previously but they are pretty funny.
Comic genius at work. This is improv and Jonathan Winters is The Master. I think he spawned Robin Williams. 
YouTube - Dean Martin and Jonathan Winters
For those of you with delicate sensibilities or who are easily offended, do yourself a favor and just skip these.
These next two aren’t exactly videos - YouTube - Bob and Tom - Donald Duck Blowjob
Monty Python - YouTube - Sit On My Face
Any Rodney Carrington fans out there? 
YouTube - Dear Penis-Funny Song
YouTube - indian cosby remix best versionthis one is the cosby show intro (India remix)
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BOXXY!!!
DONALD DUCK GETS HIGH!!
Are all Scientologists this vague? This is a total zombie.
Here you go: YouTube - Tom Cruise Scientology Video - ( Original UNCUT )
This is my husband:
LOL!!! 
Any Star Trek fans here? These are some “humorously edited” Next Generation clips that are HILARIOUS! The last one is my favorite. (They’re all on YouTube, so… yeah)
-D4
This one is just too incredibly awesome in so many ways:
