get hermit crabs! you can paint their shells and stuff and have races! i had one but uhmm, i kinda accidently killed it then my cat ate it, least she enjoyed it :|
uhmm G.Pigs are alright but i've never found they handle well and are afraid of just about everything. get a dog maybe, they eat everything so you don't really need a scraps bin and they go mental when someone comes to your front door!!
you can paint their shells but its not a good idea, it can lead to an early death