it is possible to make a file on the internet called squad.xml
what this does is when you press 'p' in multiplayer it displays a picture/logo, icq number, e-mail and all that.
Also, when you enter a vehicle the logo appears on the side.
But if you aren't associated with a clan you dont need to worry about it, although i have heard of independants making their own squad.xml files
so, what it does is tells the server where to look on the internet to download your information, but it is annoyingly hard to set up