I've been in one since the Sega Dreamcast days. That's when the clan I'm in formed. A few of the original members were in a clan called SegaGods (they died out 3 or 4 years ago). A couple of the members left SegaGods and made a new clan, called SegaDevils. The rest is history. I've known some of the people in it for 7 years now. Great group of people. We have about 20-30 active people currently and are mostly into gaming on the 360. We're trying to get some Halo 3 wars going on, but the big one most of us are excited for is CoD4.
www.SegaDevils.net is our website. We have forums aswell if anyone is interested (I go by the name of AlnitaK there). The site isn't being used a whole lot but the forums are usually active (not CP active but active enough for the 20-30 people that do post heh).