I joined ClubWPT today and they have a freeroll for an actual physical poker calculator. It has buttons like a regular calculator, but it has buttons for 2-10, J, Q, K, and A! I'm going to try to win one just for the novelty aspect.
As far as online tools I use PokerStove constantly to reevaluate interesting hands, and CardPlayer's omaha calculator. Also http://propokertools.com/simulations is a good website, it can simulate showdowns in 6 types of poker games