Tim Rosenblatt, our Director of Applications Development, has just put the finishing touches on a hot new firefox extension for Twitter users called Tw-autocomplete - No longer available. The best description possible is the one from the extension's page:

"An astonishingly simple add-on for Firefox that adds autocomplete support for @-messages and d-messages to Twitter.com"

It really is just that simple. You install and it starts working right away. Just type @ (or "d " for a private message) and start typing the username of one of the people you are following and an autocomplete drop down should appear. Tim has an even more complete description of how to use Tw-autocomplete on his blog. So if you are a Twitter user, go install this extension and start saving yourself some time!