a good friend of mine kept a "walking batfish". they can be good fish but they are very susceptible to disease and need a lot of flat area - fine sand to bury and lay on.
but they are fun and tame, will eat out of your hand in no time.
Lookdowns, need a tall tank. I wouldnt recommend them for anything less than 500 gallons. they are large reef fish, not suitable for most home aquariums.