Digital cash is paradoxical.
All this is done with patented mathematical processes invented by David Chaum whose company, DigiCash , licenses the technology. And if a couple thousand lines of C code is your idea of a good read, you could hunt down a source-code implementation of Chaum's technique called Magic Money , the work of a pseudononymous cypherpunk called Pr0duct Cypher. I hear you asking. Some people may go a bit overboard about this stuff. Timothy C. May's Crypto Anarchist Manifesto describes a future where an anonymous, untraceable economy challenges governments' ability to tax, or even exist.