Blockchain is a revolutionary technology that allows people to record transactions on a digital, decentralized, distributed ledger, without any central authority. Some consider this technology as “the trust machine” and cryptocurrency is without doubt the most notable by-product of the blockchain revolution. Initial coin offering (ICO) is a new way to raise entrepreneurial finance, newly created cryptocurrencies are being sold to the public by start-ups in exchange of capital. This chapter intends to clarify this phenomenon by explaining the concepts of blockchain technology, cryptocurrency and ICO, in order to provide valuable insights into this new trend of entrepreneurial finance.