a little canoe so they can go boating.... I was so tempted to get one of those little glittery cat balls and put in the tank...but hubby wouldn't let me...uuurrrggghhhh
ive heard of people who keep the elephant nose, a fish who uses electro pulses in its tail for navigating, communicating and feeding, put balls of tin foil on the surface. they say the fish likes to play with the balls on the surface, tossing them around with that "snout" projection. kinda cool i think.
EDIT: those fish are fit for kings you know. archaeologists have found jars with skeletons of elephant nose fish in the tombs of the pharaohs. i wish i could get one, but i heard they only like bloodworms, which i am starngely allergic to...