I found this a while back but did not have the time to test it until recently. I found it to be one of the best tools for adding keywords to your PPC campaigns.
According to the Keyword Tumbler web site:
Keyword Tumbler is a free keyword research marketing tool that takes your existing keyword phrase and generates multiple variations of it, simply by mixing the words in each keyword phrase around.
Why would you want to do this?
Well according to Amit Singhal, principal scientist at Google, a guy who really should know what he’s talking about, over 50% of the 200 million searches performed a day on Google have never been searched before!
And let’s not forget what Perry Marshall, author of the Definitive Guide to Google AdWords said at Carl Galletti’s Internet Marketing Superconference in June 2004: “Every combination of keywords that somebody could conceivably type in on Google is a market.”
Keyword Tumbler helps you build huge keyword lists in seconds!
So check out the Keyword Tumbler and see for yourself!