keepassx is a nice tool for keeping track of passwords. I also use this on Android, making keepassx a convenient choice. Install with:
sudo apt-get install keepassx
Unfortunately, there is currently a bug that results in the keepassx icon not appearing on the sidebar or when Alt+Tab is used to cycle through programs (at least in the 64bit version of 12.04 that I am running). More information on this bug is available here, as well as a fix.
To patch, find the file ~/.config/sni-qt.conf and add the lines:
I had to create this file in the appropriate place and add the desired lines. In any case, this patch seem to work for me.
More information on keepassx is available here.