The big 3 are the Beatles, Rolling Stones and the Beach Boys. During their prodigious-output heyday, all wrote way more tunes than they could record or at least put out--some contract writing, some that didn't fit their styles, some favors for friends. What I'd like is a list of songs and artists who recorded tunes the Big 3 wrote but never recorded. You make the list; I'll do the linking. Deal?
Here's a place to start with the Mersey-side Boys but it needs culling and condensing: http://www.columbia.edu/~brennan/bea...-didnt-do.html
Couldn't find a similar list for the other 2.