David Letterman has become almost unrecognizable in the short time he’s been off the air.
Letterman’s surprising retirement look

SAN FRANCISCO - NOVEMBER 25: The Band is seen here jamming at The Last Waltz with Neil Young, Levon Helm, Robbie Robertson, Paul Butterfield, Eric Clapton and Ron Wood at Winterland on November 25, 1976 in San Francisco, California. (Photo by Ed Perlstein/Redferns/Getty Images)