This one is called the SEO Book Keyword Suggestion Tool. Needless to say it's free.
As an example I entered keywords I was thinking of using on my celebrity blogs of 'Amanda Beard' - she's in the news recently.
The tool came up with a massive list of keyword suggestions - far too many for my screen shot below.

It also produced a lot of other interesting stuff as well, such as:
* Estimated number of searches, for the keywords, today on the likes of Google, Yahoo, MSN.
* AdWord estimates and costs.
* Links for keywords to Google News, Yahoo! News, Topix etc.
* Blog Search and Tag Links applicable to the keywords.
* Thesaurus, Dictionary and Encyclopedia links for the keywords.
* ... and lots more besides.

The value of such info depends on the individual but a lot of research can be done with the help of the tool.
I wouldn't use it for every post I write but I've found it effective on occasions. The only danger is that when you start messing with these sort of tools you can easily get sidetracked and forget about actually making money.
Good luck,
Mike.
Millionaire Mate: Meet successful and beautiful people. Free to join.