If you're a Windows user, you should really download Roboform. If you're like me, you regularly have to remember dozens of online passwords and usernames and to fill in all sorts of forms. Because of the varying requirements of all these sites or perhaps because certain usernames are taken, I have a whole bunch of different usernames and passwords. Sometimes I can't remember them and have to get them e-mailed to me.
That is, until I began using Roboform. It saves all that information in one spot, encrypts it, and brings it up on demand. Much more fully featured than any other form filler I've used, including the ones included with web browsers or the new Google toolbar. Did I mention that Roboform is free?