Online Sites for Creating Awesome Business...

this generator actually creates some half decent names...unfortunately you can't guide the context of the names
lightsphere

Seroius answer:  search for what domains are available and see what comes up.  Of course, helps if you have some sort of inspiration before hand.

Non Serious web 2.0 answer:  just drop a vowels, maybe add an "r" to the end and away you go.