I think the only way a business like this could work is if they were located in a large city or near a college campus, and they charged monthly membership fees like $39.95 individual/$99.95 for a clan (unlimited clan members after paying one-time clan setup fee!) Inside, they'd have to have some sort of food/beverage facilities and make money on these impulse purchases from members. Ideally they'd have Bawls and other gamer oriented drinks, and maybe pizza by the slice and other easy food items or vending machines (I imagine most hardcore gamers are of the 'eat anything' variety.)
As far as the game machines go, they should have a few Xboxes connected to the net, as well as some net-connected PS2s. I'm not sure if Live gamertags are tied to their unique xbox or not...but if they aren't I imagine anyone could login to their account on the public xboxes. The beauty of these machines is that they are cheap, require only cheap TVs, and don't require much maintenance/upgrades. I imagine they'd only have to keep a library of the most popular multiplayer games.
PCs are difficult to figure out here. On the one hand, if you just bought Dell's equipped with decent videocards you could save money by buying in bulk and probably use Dell for service and warranty, etc. But if you built your own PCs, all using the same equipment with decent motherboards, you can provide yourself an upgrade path (upgrade to more powerful CPUs later down the line without having to replace the entire system.) What might make sense here is leasing the PCs from Dell and upgrading every 12 months. I know Dell, HP, and Gateway are interested in targeting the gamer market and are setting their sights on Alienware, Falcon Northgate etc...so maybe some sort of marketing deal can be worked out with these companies (only if you plan on franchising this though.)
Once you've got all the infrastructure, intense marketing will be needed to recruit customers. Obviously you'll want to get as many clans registered as possible...and help them to schedule games with other clans around the nation to keep them coming (that's why setup fee in order to get them registered on the web, etc.) In terms of operating hours, I'd think keeping it open on weeknights and weekends only would make sense, so you wouldn't have to pay staff for 9-5 every day (unless you want to be open during the day as an internet cafe or VOIP/conference center to rent out to local businesses.) I don't see a lot of business coming in on the $39.95/month. Marketing should use the message that instead of buying a new game every month, it makes more sense to pay the $39.95 and play all the latest games on the latest hardware in a cooler setting than your bedroom (but do geeks socialize outside their home??

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