My username was Weirdo., but I got bored of it and everyone is weird anyway, so it doesn't really have any significance.
So I changed my user to Clembot.
The name of one of my favorite characters who I made up is C-13M, which looks like Clem. (It happens to be his nickname.) And he's a robot, so I put Clem and robot together, and then Clembot was born.