Joe Cocker, The Letter, originally a hit by the Box Tops
Grateful Dead, Turn on Your Love Light. Bobby "Blue" Bland first recorded
Another vote for Eva Cassidy’s, Over The Rainbow (don’t remember who wrote the Judy Garland original)
Thankyouforlettingmebemyselfagain, Magazines’ cover of Sly and the Family Stone’s terrific original
Oye Como Va, Santanas’ version of the Tito Puente original.
Laura Nyro’s version of "God Bless the Child" originally performed by Billie Holiday, Al Kooper did a passable version too with the original Blood Sweat and Tears.