In support of Project (RED), the AIDS relief charity that Bono founded, him and Chris Martin of Coldplay performed "One for My Baby", on Jimmy Kimmel Live.  You'll notice Sean Penn behind the bar too.

To raise money along with Bono for the charity, many celebrities have posted "Experience" opportunities with them, that you can bid on.  You could play mini golf with U2, walk the red carpet with Jack Black and Cate Blanchette, hang with Diddy, and more.

Get the full list of celebrity experiences you can bid on here.