Usually people picture SMS-services as part of web 2.0 or just web based solutions, but actually it is just one side of the SMS-services. Since the number of mobile devices in increasing all the time, SMS-billing has become a value adding solution. Cell phones are always with people and that is why people can pay for park, pay in shops, order a lightening to ski-track etc all the time notwithstanding how much cash does they have in their wallet.
Finns have came out with a great idea (read a whole article). From January people who are driving along highway 1 can open public toilets by sending a SMS. They explained that as a result of continued and endemic vandalism, the Finnish Road Administration has developed a system which allows travellers to open the doors to roadside toilets only by sending a SMS message to the number given by the Road Administration. So if you want to smash the toilet you’ll have to pay for that, the best part is that it is also possible to find out who as behind the vandalism. But if it was me I would use prepaid card 
