We have had the same three hermit crabs for almost four years now, and they're still going strong with very little maintenance. Once you get the tank set up properly (do the research--pet stores will steer you wrong here), there's very little work involved. They're fun because you can feed them all kinds of food, take them out of their habitat and hold them/let them run around for short stretches, and add accessories to their habitat to keep them entertained. It's also fun to see them change their shells and move from smaller to bigger shells as they age. Plus, they're cute! The biggest thing against them (in my mind) is that they're wild-caught animals.
