Bill gates gave his last keynote at CES 08, on January 6th.

Look at a different Bill Gates here:
http://www.youtube.com/watch?v=HEWMC4usElM

Also, Slash and Bill Gates jammed together to "Welcome to the jungle" at the end of the keynote.

Bill Gates is very funny with his uber geeky attitude (he just stands there holding the guitar).
You can see it here:
http://www.youtube.com/watch?v=u5WIEep8DJg