http://ajaxwhois.com/
Excellent domain search tool, ajaxified, and supports multiple (even configurable) extensions, probably not 100% reliable though if it relies on whois.
http://www.za.net/
Free domain names (without DNS) on the .za.org and .za.net subdomains. Requests require human approval and so can take a few days. Interface is plain text to email, old school!
http://www.quinapalus.com/cgi-bin/match
A great little tool. Give it a vaguely regex like pattern and it'll give you a list of all the possible words. Want 5 letter words ending in me or be, gotcha! Great for domain name inspiration. Output is scripting friendly plain text. :-)
http://www.wildwestdomains.com/
Wild West Domains is the reseller arm of GoDaddy. Same company (I think) but WWD allows you to setup a whitelabel domain reseller system.
http://www.dotomator.com/web20.html
The web 2.0 name generator from dot-o-mator is an interesting tool which generates an endless stream of Web 2.0 sounding names. Useful for name inspiration.
http://www.dotomator.com/
The dot-o-mator allows you to punch in a bunch of keywords (or it has predefined lists) and combine them to make domain names. Then with one click you can check the availability of all those domains. Very useful.
http://instantdomainsearch.com/
A great tool to search domain names. Type in as many words as you like and the results appear below almost instantly via sweet ajax interface. Very nice.
