A few weeks ago during a work trip to Baltimore, I checked out the National Aquarium in Baltimore's inner harbor. I was a little disappointed I didn't get to touch any sharks or sting rays, but otherwise I loved it. The all windows entrance was pretty stellar. And a few of the exhibits lended themselves to some pretty cool photographs - especially the tanks of jelly fish..
I remember visiting the Florida Aquarium as a teenager and loving the aquarium so much I decided to be a marine biologist. And then I realized I was scared of the deep ocean, didn't really like salt water or getting stung by jelly fish. So the whole marine biologist thing didn't happen.