Sometimes, (love it or not) covered songs were much better. Which, for me, the singer who covered the song done much much better job rather than the original singer.

For me, they are:

Kris Allen, performing Heartless by Kanye West

311, covered Love Song from The Cure

All Along Watch Towertower, originally by Bob Dylan
, covered by Jimi Hendrix

Not forgetting Dayadiarmon, singing Numb from Linkin Park.

Eh. He shouldn't be on this list.