I've been really happy with 1Password, but it seems 1Password does not have a Linux client. They have what seems to be a browser extension (1PasswordX), but so far I've hated the 1Password browser extension on OSX, so I can't imagine using that full time on Linux.
With that said, I'm super happy with 1Password's UX on OSX. It sits in the tray, can be activated with a toggle, allows me to search a password name, and then keeps that site/etc active while you toggle back and forth between the app and 1Password Mini. Copying in this manner is quick and easy. This, plus excellent support for Windows/OSX/Mobile makes 1Password a joy.
What are you using on Linux and do you enjoy it? Any problems with it?