How to make a billion in tech T hese men below are all billionaires. Want to know how to be rich? Find out about the bright ideas and innovative thinking that got them to top of the tech ladder before anyone else Mark Zuckerberg: Facebook Estimated personal worth: $4 billion How it all began After being dumped by his girlfriend, Harvard computer science student Zuckerberg proceeded to get drunk and spend the evening turning his programming talents to Facemash, a website that used hacked photos from the Harvard college database -- which was called Facebook -- to let fellow students rate each other as "hot" or "not". Bright idea Facemash was shut down fairly quickly by Harvard, but not before gaining notoriety around campus. Student rag The Harvard Crimson picked it apart and suggested the possible benefits of having a, somewhat less judgemental, online campus community. The success of Facemash inspired Zuckerberg to build TheFacebook, enlisting the help of dorm mates Eduardo Saverin, Dustin Moskovitz and Chris Hughes. It was to be an informal place that could be used to contact other students, as well as a place for sharing photos and personal interests. What happend next Within 24 hours 1,500 students had signed up. That was 2004. Zuckerberg bought the domain name Facebook. com from Harvard for $200,000. That was money well spent, as Facebook has since branched out to connect people across the globe. In 2009 it connected a staggering 400 million users, banking a revenue in the