You might have already heard "Why Even Try," the slinky duet between Theophilus London and Tegan & Sara's Sara Quin. The pair visited Letterman last night to do the song live. I like the band's LVRS hats, a hat tip to London's new EP. Watch: [videoembed size="full_width" alignment="center"][/videoembed] Grab the song: Theophilus London - "Why Even Try" (Feat. Sara Quin) ...