KeePass Password Safe

KeePass is a free/open-source password manager or safe which helps you to manage your passwords in a secure way. You can put all your passwords in one database, which is locked with one master key or a key-disk. So you only have to remember one single master password or insert the key-disk to unlock the whole database. The databases are encrypted using the best and most secure encryption algorithms currently known (AES and Twofish).

The database (*.kbd file) can be access from Windows and Linux systems.

Get KeePass

Installation on Ubuntu

The Linux port is named KeePassX and has its own webpage.
Unfortunately, the version that will be installed from the applications main menu isn't the newest, so you should add the following repository to get the latest version:

sudo -i
echo "deb hardy main #SniperBeamer (KeepassX, ...)" > /etc/apt/sources.list.d/sniperbeamer.list
apt-get update
apt-get install keepassx