There is zero chance governments are going to tolerate this once it grows beyond a certain scale.  Their power to tax and control your lives rests upon their iron grip on money and banking. Their squeals about "criminals" using this system divert your attention from the fact that tax resisters are also "criminals" in their mind.  Bitcoins, and other variations of this theme give people a chance to store value and transact business outside the government's control.  Governments will hate this and do everything they can to crush this.

Therefore this is a great idea.  Give Uncle Sam (and his inbred kin folk) all over the world, a big fat middle finger and keep on truckin'.  Crash the $, crash other fiat money, and maybe, just maybe, you'll achieve liberation.