I'm surprised nobody has mentioned this yet....
Last week I was in Sam goody and I saw a GRP compilation of Beatles songs in the listening tower, and guess what? "I Want You" by Groove Collective! I was kind of disappointed though, partially due to their overly percussive and choppy interpretation of the really heavy part, and partially due to the fact that the production on the song was so much cleaner, with the result being that they really sounded more like a 'modern jazz' Spyro Gyra thing than a sloppy funky groove band.
Jay B
P.S. There are, in fact, some other fairly impressive straight jazz versions of Beatles songs on the album so check it out regardless...