Spent a week on a cruise down to the Yucatan with the family. We went snorkeling across the reefs off the south side of Cozumel. Totally awesome! I've got to do that again. On the bright side, snorkel gear is pretty cheap. On the bad side...getting to anywhere that has water clear enough to do it is expensive!
I'll be over in Oman and Iraq this Fall and Spring. There's supposed to be some nice water in the gulf over there. Muscat is supposed to have a large paintball group as well.
A couple pics...view across the southernmost point of Cozumel from the top of Punta Celarain Lighthouse, and our snorkeling group off the coast (me with the hands up).