I mostly make my usernames up when I make an account for something. Here are some I use (mostly historical since I don't play games as much):
* Lastrador and sorrilius on Alter Aeon
* Rayman on Materia magica
* Regentron / Ferrumite on the forgotten islands
* The frisbee of peace on crazy party, I'm not sure about the exact case and whether the "the" is there, but it shouldn't matter much.
* headphonejack on the playroom
* ferrumite on RS games, although I wanted to change it for a while now, only thing preventing me is the fact the game got corrupted on both my laptops and I don't even log onto it much anyway
* Nocplusten on undead assault, all servers
* Regnum on erion
Please note that I might forget to update this post, so don't be surprised if you see someone with a username not mentioned here claim to be me. It's most likely me. Also most of these are historical, if I ever return to alter aeon I'll probably make a new character and same for the other muds. Also rest in peace undead assault.