In the spirit of today's post, I give you another site of the day. Bugmenot is site that is really useful. You remember those annoying sites that ask you to register every time you want to access some section? Bugmenot has a database of such sites, and provides login info to bypass the registration quickly. Of course, this is for only the free sites, it does not let you bypass premium/paid sites.
Bugmenot also features an extension for Firefox, which makes it a snap to use it. There are plugins for IE also, but I've not tried them.