65,535 - that is the limit of unique TCP/IP ports that's currently allowed on most systems (since port number is a 16-bit integer value) If multiple currencies overlap in port numbers, or if future coins use some other mechanism to connect to their peer networks you could always have more, .
In 2007, its founders were ranked as the second most generous philanthropists in America, and Warren Buffett the first. As of May 16, 2013, Bill Gates had donated US$28 billion to the foundation.
Bloomberg calculated that Gates would have a net worth of about $150 billion if not for donating large portions of his wealth to charitable causes. Bezos has been giving away Amazon shares worth about $500 million every year since 2002.