Best known as the man who spent thousands of bitcoin on pizza, Laszlo Hanyecz was a Florida-based coder who first translated Bitcoin (then available only for Windows) into MacOS. 

Joining the project in April 2010, Hanyecz quickly announced an interest in running Bitcoin on his iPhone, but it would be his May 2010 decision to pay 10,000 BTC to anyone who would buy him pizza that would mark his most significant contribution. 

At the time, Bitcoin had an established price (less than a penny), and bitcoin had been bought and sold, but no real-world product had ever been purchased with the fledgling currency. 

Hanyecz’s time with the project would be brief, however. He stopped contributing in August 2010 but has resurfaced from time to time for interviews, most recently in 2009 for the news show “60 Minutes” where he discussed his bitcoin pizza purchase.