First, some funny stuff:

A picture of some typical Mac OS-users!
Hamsterdance - A dance page with hamsters dancing on the page.
Movie mistakes: For example there is a Stormtrooper that hits his head on the doorway in Star Wars! Really looking forward to Episode 1 BTW (BY THE WAY)! The effects are going to be awesome
All Your Base Are Belong To Us - This is a classic on the internet. I quote this to my friends and family all time. They don't get it and that makes it funny!!
Stickdeath Really great games that I play on my lunch break. WARNING! S(t)ick humor!!!!

My favourite useful links:

Google. A really useful link, but scary since they log everything you do, and the one who pay the most can see what exactly you have searched for. Some times I therefore use Altavista.
Passagen. You need to know Swedish, unfortunately. But it is probably the funniest page on the web. It is like a digital Las Vegas. Check out "Skiss and Giss".
Piratpartiet. It is like a digital resistance movement, like in The Terminator, The Matrix or The Demolition man.
www.conspiracyplanet.com. You have to watch out. Never trust the Government.
Software downloads site. Legal, great sharewares (NOT warez)
mIRC - My favorite chat protocol. Here you can talk about sharewares and not trusting the Government.