City of New Orleans - Arlo Guthrie
Halleluja - Jeff Buckley, KD Lang
Gentle On My Mind - Glen Campbell (I actually get hives if I have to listen to GC, and I absolutely prefer John Hartford doing his own song, but GC did kinda make it his own to many folks.)
Me And Bobby McGee - Janis Joplin
As to eye-poppers, Johnny Cash in the American series doing stuff like Hurt, Bird On A Wirew, etc.

JimB