The Funk Brothers
If you have the chance, and $2.99 for the itunes rental, check out Standing in the Shadows of Motown. This documentary chronicles the work of Detroit's 'Funk Brothers'. These are the unsung studio musicians that defined the Motown sound. Marvin Gaye, The Temptations, The Supremes, etc. The Funk Brothers backed them all.
It's fascinating to hear about their respective talents. Particularly James Jamerson's bass playing, which is beyond reproach. Sadly, most of their contributions have gone widely unrecognized. Makes me wonder how many phenomenal studio musicians are out there toiling away in relative anonymity.