The most pressing problem, as I see it, is to get a digital cash system that makes it possible for people and small businesses to pay each other fast and without
registration and supervision from a big company/government.
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What is wrong with the follwing "standard" system. A central bank/government issues a currency like today. It sets up servers around the world to validate transactions.
So the solution to avoiding a big company/government regulation is a big company/government?
It is currently possible with Bitcoin to do transactions which are practically instant particularly if you do not fear some vast conspiracy to defraud you.
If you really do have need of transactions faster than Bitcoin can offer, use a different system, but you will probably have to forgo some of the benefits that Bitcoin currently offers.