Confirmed:
Locke - the Others sure view him as something special.
Hurley - can see dead people, can see Jacob's Cabin.
Desmond - the rules don' apply to him.
Walt - appears in places he shouldn't be.

Possible:
Richard - doesn't age?

Richard also told Juliet that she was "special", though that might only refer to her medical skills.

Anyoe else?

I was wondering that too. At first we thought only Walt and Locke were special... but now it seems like possibly all of the survivors have some special quality that led them to the island.