Steve Jobs got himself enrolled in Reed College in Oregon, but one semester later, he dropped out.

Reliance founder Dhirubhai Ambani was only 16 when he left for Aden to work as a clerk owing to financial issues in family.
Master blaster Sachin Tendulkar never attended a college
 Steven Spielberg was not known for his academic excellence. Interestingly, he even failed to get admission into a film-making institute!

 WikiLeaks founder Julian Assange attended the University of Melbourne, majoring in physics and mathematics. He received only a minimum grade for math and left the university soon to start his own venture.

After the wonder effect of Facebook, Zuckerberg packed his dreams and left Harvard to relocate to Silicon Valley.
After scoring a near-perfect 1590 on his SATs, Gates enrolled at Harvard but left without a degree to start Microsoft Corp.
source:http://in.omg.yahoo.com/photos/famous-school-college-dropouts-1318107175-slideshow/gates-photo-1318106909.html