Ryan Stout created a wonderful tool that will help you find the right domain name for your new site.
It is called Bust A Name and has a nice JavaScript interface that includes a rails, MySQL, and lighttpd backend.
Primarily a word-combiner, once your words have been entered, you can choose similar words from a dropdown list. You can sort domains alphabetically, by readability, length and alphabetically. You can also group keywords to ensure that they are not mixed together. You can also select from a limited set of suffixes or prefixes, and you can add or remove the last vowel.
This tool has helped me a lot to find usable domain names by augmenting the similar words feature with a Thesaurus, and finding additional keywords with Google’s Keyword Tool.