I've had a few names in my various times here...
Steaver - Simply a slight play on my real name.
Steaver370 - The "370" comes from the Socket 370 connection in Pentium 3 type computers, which I happened to be obsessed with AGES ago when I made an email adress and "steaver" was taken, so I put "steaver370". I still use the number 370 sometimes, although the name "Steaver" is long since dead in most places.
Streetlight Admnistrator - An obsession with streetlights at the time. As for "Admnistrator" (which is a deliberate misspell of Administrator), it was just to look cool.
Sunrise - It's the name of my fav song at the moment(and it's been my fav for nearly 7 months now). That's all there is to it. If you're wondering, it's sung by a japanese band called Puffy (known as Puffy AmiYumi outside of Japan to avoid name conflicts with a (crappy) rapper)