Bob Dylan has done a number of songwriting collaborations over the years with partners as varied as Jacques Levy to Michael Bolton. There's even been some imaginary Dylan collaborations, such as his mythical team-up with ex-Monkee Mike Nesmith to supposedly create Nesmith's song Rio.
Here's a real Dylan collaboration with an unusual twist. Dylan originally developed Rock Me, Mama, a.k.a Wagon Wheel, during the 1973 studio sessions for his under-appreciated movie soundtrack album - Pat Garrett and Billy the Kid. As with many of the songs recorded during the Mexico City and L.A. sessions that produced the movie's soundtrack, Wagon Wheel never was completed much past a basic melody and the refrain,
Rock me, mama, like a southbound train.
Rock me, mama, anyway you feel.
Rock me mamma, like a wagon wheel."
As noted in a Wikipedia article, the inspiration for Rock Me, Mama probably derives from Arthur "Big Boy" Crudup's original song of the same name, although I couldn't find any evidence of the writer's assertion that any version of Crudup's original ever contained the line, "roll me like a wagon wheel."
In any case, Dylan's take on Rock Me, Mama was left off the final release of Pat Garrett and Billy the Kid, but surfaced in the bootleg Peco's Blues [sic], which can also be found under the alternate title Lucky Luke. As an aside, if you can lay your hand on the bootleg under either name, the completist Dylan fan will probably find it rewarding, as it contains several nice instrumentals that never made it to the finished album, plus lots of studio chatter from the recording sessions.
Ketch Secor, a member of one my favorite Americana/Roots groups Old Crow Medicine Show, must have come across Rock Me, Mama at some point and revised/finished the song under the title Wagon Wheel. The adaptation was obviously done with Dylan's blessing, as the copyright reads: Wagon Wheel by Bob Dylan and Ketch Secor (Bug Music, BMI).
The band apparently was performing a version of the song as early as 2001; one of its first uses was to commemorate Dylan's 60th birthday during an OCMS live performance in Nashville. Wagon Wheel was officially released on Old Crow Medicine Show's 2004 album, O.C.M.S. The song was one of the hit singles of that hit album (and a major hit among Americana fans, selling well over 100,000 copies), and numbers among its fans Garrison Keillor, who regularly requests Wagon Wheel during Old Crow Medicine Show's frequent appearances on A Prairie Home Companion.
The above is the "official" video of Wagon Wheel, with a slightly ribald 1800 hootchie-cootchi flavored carnival theme. As a special bonus, look for a cameo by OCMS friends and sometimes collaborators, Gillian Welch and David Rawlings.