Colonel Potter

I had a dream the other night that I was on an exceptionally large, sprawling deck attached to what was, I believe, a dormitory. With me was the entire staff of the M*A*S*H 4077th (in character, not as the actors themselves). Suddenly, there was a violin crescendo and I was in a Broadway duet with Colonel Sherman T. Potter (again, the actual Col. Potter, not Harry Morgan).
After a few days of wandering the house humming the song that we performed together -- of all the good songs in my dreams that I couldn't remember to translate to guitar the next morning, this I remember? -- I started thinking: what are some of the other "missed opportunity" songs or collaborations? Here's my tentative list (which will soon be updated with the songs mentioned):

Gnarls Barkley recording John Mayall's "Little Girl" -- Personally, I think this song would be amazing if recorded by Gnarls Barkley, plus I'd enjoy being one of the only people who know that it's a 30+ year-old tune by one of the greatest blues lineups in history (this being from the "Beano" album by the Bluesbreakers w/ Eric Clapton).

Otis Redding recording "To Love Somebody" -- This was actually supposed to happen, as the Bee Gees were commissioned to write this song specifically for Redding before his untimely death. The Bee Gees recorded at least the second-best version of the tune, a step above Michael Bolton's and below Nina Simone's (whose rendition will be included as a download soon).

Steve Winwood joining the Jimi Hendrix Experience -- Winwood played organ on "Voodoo Chile" and was apparently being courted by Hendrix to become a full-time collaborater in the most non-aggressive courting seen since the days of "look but don't touch" chivalric love. The notoriously shy Hendrix never worked up the nerve to ask Winwood, and one can only imagine what a Traffic/Hendrix combo may have been like. Personally, I think both band's work has not aged well and a partnership probably wouldn't have held up any better, but at least Winwood would have had a badass guitarist and Hendrix would have had access to one of the best blue-eyed soul voices of the 60s.

Thoughts? Concerns?