I'd like to hear some of your suggestions for the best and worst cover songs ever made. I'll start things off.

Covers better than the originals:

AC/DC:
Baby Please Don't Go (Big Joe Williams)

Jimi Hendrix:
All Along The Watchtower (Bob Dylan), Johnny b. Goode (Chuck Berry)

Showoff:
Borderline (Madonna)

Dave Mustaine
School's Out (Alice Cooper)

I'll post some of the "worst" later... there are too many too list!