Important: I'm too busy with my own company to do diligence on new angel investments at least until mid 2014.
I've started six companies (with one sale, two IPO's to show for it), I've been doing this for 30 years you get the benefit of learning from my mistakes.
I founded CyberSource. Faced with a business (Beyond.com) that was getting over 50% credit card fraud on our orders I designed and built a fraud detection system. We spun that out as CyberSource, took it public (along with Beyond.com - a two'fer) CyberSource was later acquired by VISA for $2B.
So from one startup (and one set of investors) we had 2 IPO's, a feat I have not seen repeated anywhere.