Another thing, don't think this is an invite to use trademarked names. As tempting as it is, it just is not worth it. You can attack a great trademarked keyword without having to register a trademarked domain name. Research it first by all means though as some names are more usable than you think, but you better ask permission. I have found a few myself that allow this, but it took some research and emails. When in doubt though, stay on the safe side.
Also if you don't own Market Samurai, yet, you really should consider making the investment in it, it is a solid tool.