The magical fish in Fish Tycoon each have a special quality. If you mean in Virtual Families, they do nothing but remind us of Fish Tycoon while looking pretty. hehe

Only a core gamer could come up with entertainment so appealing to gamers and non-gamers alike. You just gotta love that Arthur's "resume" on the main site includes that he had a level 70 Druid! I had played one of the games and never heard of the company, so I visited the website to see just who the heck they were. That part made me grin (and I knew they'd be successful.)