Nobody has mentioned two that seemed to be recommended a good deal: a rat (although I'd say my wife would be completely against it anyway just because of what it is) and a lizard (leopard gecko or bearded dragon). Anyone had experience with either?
DD14 has both aquatic frogs and a leopard gecko (two different tanks). The frogs are pretty much a desk decoration, but DD14 really likes the gecko. Feeding time is fun as Avari (the gecko) totally attacks the food you put in her cage. She'll also run to the front of the cage and excitedly watch whenever one of our cats wander through DD14s room.
Initial set-up can be a little pricy, but once your tank is set-up, water, crickets, and vitamins are quite affordable.
Best of luck,
--S.F.
