David Bowie at The Concert for New York City gave the finest rendition of "America" that I have ever heard. The song was written by Paul Simon and recorded by Simon & Garfunkel in 1968. The Concert for New York City, held on October 20, 2001, was a benefit concert in response to the September 11 attack. Organized by Paul McCartney, the concert raised money for charity and honored the first responders from the NYC Fire Department and the NYC Police Department.
(Unfortunately, during the time since this was first posted, the YouTube video below has been removed, but I found a copy of the same video at Daily Motion which you can watch at http://dai.ly/x8s3su)