Ethereal

Fancy showoff stuff

All sorts of things. Love potions, potions that give you cat ears.... The list goes on.

^ What they both said. Vanity potions are fun, because you can do fun things with them, as long as they do not affect battle. So like Hakai said, you could make love potions, for Halloween I had potions that changed my hair and eyes temporarily. You could make potions for pranks like stink bombs.. its really whatever you want as long as it does not alter your gender, stats, or affect combat.