phpMyAdmin is a very nice MySQL administration tool. I use it for users and grants, rather than creating actual databases, but it has almost every feature you could desire from a MySQL administration system. It's consistently one of the top-downloaded projects on SourceForge, so I guess I'm not alone in my appreciation of it.
If you're a MySQL hacker, I strongly recommend it. It's one of the reasons I always build Apache with both mod_perl and mod_php. (Roll on Perl->Parrot and PHP->Parrot!)