Keyword research

WebmasterFeed.org:

Create keyword lists from websites A tool that lets you create keyword lists with prices from any website you're visiting
Finding Keywords for SEO - all your tools suck Andrew Johnson recommends only using the keyword tools to do keyword discovery and then run PPC campaigns to obtain real data
Wordtracker Free Keyword Suggestion Tool Generate up to 100 related keywords and get an estimate of their daily search volume
Wordze Keyword Research Tool In case you're looking for a serious keyword tool now when the Overture keyword suggestion is gone