The cyber currencies which try to look like traditional currencies will be shut down by the government while they have the power to as stated in other comments.

The cyber currencies which try to look like traditional currencies will be shut down by the government while they have the power to as stated in other comments. However, I see couch-surfing in a way, as a very lose cyber-currency. It has its limitations: there is only one kind of product in the market which uses the currency, and the amount of the currency you have isn't exactly quantifiable. Still, you can use it to trade services at no cost (or very little) and flies under the radar since there is no exchange of quantifiable value taking place. Reputation becomes a new lose currency. Also see LETS systems which are actively, legally in place around the world.