We were all drawn to applying the statistical, experimental, and algorithmic approaches we learned in graduate school (and in our spare time) to a range of problems in industry. Every project has a big learning component that keeps things exciting and fresh.

Our first handful of clients all came from our professional network. I've been a developer and consultant for a long time (shockingly, over half my life!) and so, despite selling my companies and heading to graduate school, I had a bit of a network of other founders who knew me and were supportive of the new venture.

A few lessons learned, in brief: (1) Try really, really hard to be specific about what you offer (even when in reality you offer a lot of different things), (2) Write great proposals -- they become the project bible and really help streamline client conversations, and (3) Understanding a client's data and business always takes longer than you'd think.

Wanted to do something similar in cloud computing. Couldn't figure out how to get clients. Best of luck!