One of the services many people have paid for and love is RoboForm. It is a password generator and manager. Their main service was pay once and you get their service for life. Everybody that had paid for RoboForm once in the past could get all the updates and new releases for free as long as they had paid already once in the past. Resently they came out with some new features and discontinued the service on their older release and required everybody that had paid already once before to pay again if they wanted to receive the newer version and updates. So much for paying only one time. The good news is that there is an alternative to RoboForm. LastPass is very similar to RoboForm and best of all LastPass is free for everybody and unlike RoboForm, LastPass works in linux.
One of the things that never seems to amaze me is how the paid services and products are only supported on one or two of the major platforms (Windows® and Machintosh®), but the free counter parts are many times able to run on 3 or more, meaning they can run on Linux and others as well many times. The way LastPass works is by keeping track of your websites and passwords. It will generate long strings of very secure passwords also, so you don't have to try and remember your passwords. No more continuing to have only 3 passwords for everything you do. Here is a password I just generated in LastPass - fC08p0Jk33p8eV1Mk1. Now all of your passwords can be that strong and all different, all the time you only have to remember 1 password and that is the password that will allow you access into your LastPass account, hence the name LastPass, meaning the password you set to allow you access into your account will be the last password you will ever have to remember.
You can load LastPass onto a USB stick and take it everywhere with you also, but that is not even needed if all of your passwords are for accounts on the internet, you can simply just go to their website and you can access your account with all of your managed sites and passwords there. It will automatically fill in forms for you also if you want it to. Even though LastPass is free, it is not open source so if you are someone that is wants to only use open source products and services as much as possible there are alternatives available, but I have not tried them yet. I will post more about those at a later date.
https://lastpass.com