I'm going to be starting a premium (pay) service for one of my sites that will cost the user around $1-$2 per month. The majority of the users are in the 15-25 year old range and since those under 18 probably won't have a credit card, but very well might have a cell phone, I was wondering if there was such a thing as a payment processor that would allow the user to send an sms message to a number, and they would then be billed on their phone bill.