Any name that is brandable. In the last week I sold the following:
SpecHouse.com $850
GreatPads.com $1,300
BadCall.com $1,200
UserBank.com $1,750 (Pending)
Short and easy to spell. Very little traffic. It's pretty easy if you have a good eye. I have thousands of names like this....it's like having a printing press. With brandable names you always know what you are getting....better than the phoney stat scams. I made money and the buyers got great deals as well....everyone wins.