This document discusses bitcoin mining websites as a potential future of website monetization. It provides an overview of bitcoin, explaining that it is a digital cryptocurrency that was created in 2009 and can be mined through computers solving complex math problems. The document then discusses how websites can implement bitcoin mining through JavaScript scripts to convert visitors' computing power into bitcoins earned for the site owner. However, it notes that JavaScript mining is very inefficient. The document encourages informing and allowing users to opt-out of mining on sites.