His name is Bartimaeus. I named him after the main character in the "Bartimaeus" trilogy by Jonathan Stroud. Problem is, "Bartimaeus" is something of a mouthful of a name for a fish, with the result that no one calls him by his name. To begin with, mom was calling him Barti, which I objected to; I said it reminded me of a certain someone I dislike in J.K. Rowling's "Harry Potter" books. So, we turned to simply calling him Fishy. Wonderful name.
Then, I had this great idea - why not call him Maeus? Nothing against "Fishy," but it's sort of bland. Maeus is short and sweet, and works. Not only that, but it's exactly the last half of his name! :) So, that's what we call him now.
As to what he's like...gosh. If you've read the afore mentioned trilogy, you'll know that the guy I named Maeus for is quite a character. (Don't worry, I won't give away any plot for those of you who haven't read it.) Well, Maeus seems to know who he's named for. True, about all he can do is swim around his tank, but even then he can do some weird things. He likes to do acrobatics, and sometimes swims upside down. No, I don't have a dead fish on my hands who I only think is alive. He seriously does swim upside down often enough.
He is just silly and funny to watch. :P