Wow, this is an interesting site (though possibly not safe for work). College Humor has put together a list of what has to be about 75 sites that have gained fame throughout the years...from "Chocolate Rain"...to "Numa Numa"....to "Angry Ginger Kid" (no relation) to the "GI Joe Spoofs". This is apparently a part of their site that has been up for years, but I hadn't seen it until today. Definitely very cool to see many of the Internet memes put together in one place. At one point or another, I have seen most of these things show up in my mailbox or over an instant message.
Warning: This may suck hours from your day.