Lyrics: [Paul Simon]
Music: Grateful Dead/Paul Simon
A jam by the Grateful Dead supposedly based on Paul Simon's song "59th Bridge Street Song (Feelin' Groovy)." The best example is played as part of Dark Star on 13 Feb 1970 on Dick's Picks Vol 4 at about 18:20. The connection is pretty tenuous: the chords aren't quite the same, but Jerry does seem to quote a bit of the melody.
The same recording features on Greyfolded on the track "73rd Star Bridge Sonata."
See the essay on The Dead's Early Thematic Jams in the Grateful Dead Guide for more information.