So sad to hear about the death of Robin Williams at 63. I'm respecting the wishes of his wife and family: bypassing how he died to celebrate his life. 

Aside from his great film work, I always thought he was at his funniest on talk shows. Here's two amazing appearances. 

2009 with David Letterman

 

This was just last year with Craig Ferguson. Just a warning, this one's a bit naughtier as it's late late night.

 

And then there was this unforgettable appearance on "Inside The Actor's Studio" (if you can find the full video watch it if you can)