Show me your viral videos!

[Beentown]

Show me some of the best viral videos you have seen. I will start:

[video=youtube;dMH0bHeiRNg]http://www.youtube.com/watch?v=dMH0bHeiRNg[/video]

And one that fits my hobbies:

[video=youtube;foZlciP6gUQ]http://www.youtube.com/watch?v=foZlciP6gUQ[/video]

Mythbusters is going to do this one supposedly.

Beentown