That's what I was going to say. Do it in a specific location, do a really good job of it, and make sure it really 'takes off' in that location -- and all the while you're doing this keep thinking of how you can enlist the support of others to 'go global' when the time comes.

You'll have money to burn in this venture because every business in the area will want to pay you $5 a month in advertising fees to be there. Basically you're creating a whole new advertising venue!