I used pcorral for password safe on Windows. It's a nifty little program that allows me to carry around my huge list of passwords safely on a USB stick. When moving to Ubuntu, I wanted to do even better - something that allows me to do it cross-platform. Eventually I picked KeePass, which is a .NET program, so it can be run easily on Windows and Linux.
KeePass requires Mono 2.2 or higher on Linux. Since Jaunty only has 2.0.1 (Karmic is on 2.4), I had to enable the PPA source (monoxide) to install the newer Mono build. After that's done, KeePass was up and running in a minute. Cool!