Sticky Password ($30, 30-day free trial) helps you manage your ever-growing collection of passwords. I have about 400 of them stored in Mozilla Firefox, and I doubt I'm atypical. Many are useless or outdated; far too many are identical or similar. It's easy to slip into very bad habits, and to forget that even if you don't care if your log in to a minor blog site is hacked, you could lose it all if you use the same password for something more important. Further, you have passwords and codes for things other than Web sites--bank accounts, home security, credit cards.
Lamantine Software recognizes that most of your password-related activity is going to be on the Web, and puts browser integration front-and-center in Sticky Password. It fetched stored passwords from my copies of Google Chrome, Microsoft Internet Explorer, and Firefox--and can work with many others, including Flock and Maxthon (but unfortunately, not Opera). When integrated,Sticky Password will attempt to auto-fill forms with stored log ins and will detect when you've entered a new log in or used a different password, and will offer to change it for you. You can choose not to use this integration feature; I've found it works with most forms, but not all.
Of course, you need a password for your passwords. With Sticky Password, you need to remember only one, so it ought to be a strong password, a long and complicated string that takes advantage of all the oddities your keyboard has to offer. The password file itself is encrypted and useless without you manually entering the key; this makes it safe to back up--which you'd better do, once you've memorized one password and forgotten all the others. To help you create new passwords (or change your old ones to something other than YourPet'sNameHere) Sticky Password includes a straightforward generator that can be set to include or exclude various characters.
Sticky Password includes a portable version, so that you can take your passwords with you on a USB drive. Because of the encryption, they're safe so long as your master password can't be easily cracked or guessed, though I wouldn't recommend storing, say, nuclear launch codes. It also can be set to auto-lock after periods of inactivity, which is vital in a shared environment such as an office.
My complaints about Sticky Password are minor. You have a single database, while other programs allow multiple databases. The interface is split between Manage Database, Password Generator, and Settings, each of which must be invoked separately from the taskbar icon. Auto-filling of passwords can be sporadic.
Sticky Password is very comparable, feature-wise, to KeePass, which has the advantage of being free and the disadvantage of not being quite as browser-aware. My very subjective personal experience after using both is that I find the user experience of Sticky Password preferable, but I am still very much on the cusp of whether or not it's preferable enough to be worth paying for. With a fully functional 30-day trial, there's ample time to decide for yourself.