KeePass, the only open-source app on our list, is a password manager for users who know their way around a PC. For example, when you install KeePass, a wizard asks you where you want to store your database. KeePass makes that database easily portable -- you can transfer it to a USB drive and connect to another PC. AES and 256-bit Blowfish encryption provide reasonable assurance that your data won't be compromised if the drive is lost or stolen. You can also keep it in the cloud provider of your choice. The mobile and desktop apps synchronize directly to Dropbox or Google Drive.
KeePass is lightweight -- it doesn't store file entries, registry keys or INI files on your PC, and it even clears the clipboard on exit when the enhanced clipboard protection option is enabled. KeePass is OSI-certified.
Open-source software for a password manager has pros and cons. On the plus side, it lets savvy users check the code to ensure the software performs as advertised and there are no backdoors. This is good for coders who like to tweak a setting or two; for example, choosing different encryption algorithms. On the other hand, granular features are not necessarily what most users want in a password manager.
KeePass is available for Windows, Mac OS X, PocketPC and Smart Devices, Windows Phone 7, iPhone/iPad, Android, BlackBerry, and Palm OS.
Price: Free (donations accepted)