BloggerMan = Blogger, because that's my favorite word, and man, because... actually, I don't know why I put man. It's just a name I thought of really quick because I thought I'd only be posting once at UBBDev.
I've also had:
SkaBryan = Ska, because I like ska, and Bryan, because that's my name.
HylianLink = Link from Zelda... and he's Hylian, so... yeah...
Maximus241 = Maximus is the nickname a friend gave me (which lasted for about 2 minutes), and 241 from the RBF song.