Skip ahead Buying a large amount of bitcoin: What are the options? Founded in , Kraken is a digital currency exchange designed to suit serious traders. Please don’t interpret the order in which products appear on our Site as any endorsement or recommendation from us. Buy or Sell? In , bitcoin miners began to use computers designed specifically for mining cryptocurrency as efficiently as possible, called Application-Specific Integrated Circuits ASIC. Although these payment methods all perform the same function—exchanging traditional currency for bitcoin—they each carry their own set of fees.