Butt coin

Bugger Bitcoin, it can be brought down if a few servers are taken out.

I reckon there needs to be a new virtual currency based on the fempto-second elements (ununtrium (Uut), ununpentium (Uup), ununseptium (Uus) and ununoctium (Uuo)) that can only be detected through traces of their radioactive decay.

Very virtual and yet based on real and hard to get elements, with an exchange rate of about a billion dollars per transient fempto-unit.