I do a lot of keyword research online, and even though I use a couple paid options I am always looking for new ways to come up with results for the niche products and sites I create. I have compiled a list of all the sites I tend to visit from time to time and thought maybe other marketers would be able to use it for their keyword research.

FREE Keyword Tools:

Lycos own list of the 50 most searched keywords

http://50.lycos.com/

Search funnels with Microsoft. Here you input a keyword and choose if you want to get results that starts with the word your are searching for or ending with that word.

http://adlab.microsoft.com/searchfunnel/

Great domain searcher that lets you type your word while it checks the availability, but only for.com and.net

http://www.ajaxwhois.com/