I always try to find something at least tangentially related to what the project is supposed to do, and then work out a way to creatively misspell it to avoid potential trademark problems.
If that doesn't turn anything up, I'll try and construct a silly recursive acronym that has more than one meaning. Bonus points for getting something with both a rude expansion, and a completely benign one. Failing that, I either pick something that has a cool logo associated with it, or that's just so plain bizzare and silly, that no one will ever forget it.
I really do have too much fun coming up with names for things.