Trying to recall which username and password you use for which web site, or if you even have a log in to begin with? Firefox 3 includes a built-in search function for the saved passwords.
To check it out, go to Tools, Options and then the Security Tab. Then click on the "Saved Passwords..." button under the Passwords section.
Enter a full or partial search term and find that elusive username and password. (Firefox 3's official release is scheduled for tomorrow, June 17th.)