Here's another app I coded a long while ago for a client, this I'm sure will be useful to a few of you.
The program's called Domain Scour and basically it searches the DirectNIC database for domains matching your search query(ies), then sifts through and delivers only .COM's, optionally those without hyphens, and within a specified length.
http://www.dynamixxx.com/complete/software/Scour.exe