Niche Examiner Info
Niche Examiner is a sophisticated tool to help you with keyword research. It lets you build keyword lists, see how many times each keyword has been searched for, and display the number of results in Google, MSN and Yahoo.
By giving the number of times searched vs. competition, you can get an idea of how profitable a certain niche is. It is very simple and straightforward to use.
Here's a screenshot:
