The application is especially useful for users who share a computer, because you merely have to choose your username from the program interface, and Mozilla will start with its default settings. When not using Firekup, you have to leave the accounts of other users and identify yourself with your own.
The program will allow you to create as many accounts as you want, use custom avatars for each, support them, copy them and save them for later.
Firekup will make surfing easier to all those Mozilla Firefox users who have to share the computer. It's very useful. You only have to login once and, from then non, the browser will automatically enter your ID and password in each website you'll visit.