I think it would be useful to build up a list of tools which can assist with keyword research and SEO. Here's a couple I have found useful to get it started. If you've found any good tools, please share.
Overture Keyword Selector tool, good for finding out what search terms people are using.
http://inventory.overture.com/d/sear...ry/suggestion/
Another keyword tool similar to the overture one.
http://www.nichebot.com/
Google keyword tool
https://adwords.google.com/select/KeywordToolExternal
Seochat.com has quite a few different tools that are quite good.