How liquid are bitcoins and other crypto-currencies ? (i.e. How easy is it exchange them for normal currencies or for goods and services?) For example, in the USA, a person with foreign coins (of the physical variety) can't go into a typical bank and exchange them for US currency. Is getting USA currency or other national currency in exchange for crypto-currency a big problem? What merchants accept crypt-currency in exchange for goods? Do the people who honor crypto-currency form a subculture or sect of some sort?