IF you haven't already done so, look up the Baltimore Aquarium's program that allows you to dive in the exhibits! It's a blast. It IS a bit pricey, but a very cool "it's winter and I'm dying to dive ANYWHERE!" kind of experience. The two exhibits you dive in are both wonderful, one is the reef exhibit and the other is the ray tank. The staff is really cool.
ACTUALLY, given that you live in the area, you could consider becoming a volunteer there. They ask for one day every two weeks IIRC, and you get to feed the fish and everything. I live in SW Virginia, if I was just a little closer I'd totally be doing it.
Ike aka "will be back in the winter"