Professor Christensen gave this talk (or one very similar) at Business of Software this year. He was phenomenal.

One thing I like a lot about the culture in younger companies, especially in tech, is that while we are conscious of the appropriate financial ratios, we're not driven by them. For example, Fog Creek, while profitable, isn't driven only by profit, and happens to be passionate about giving developers a great place to work and helping developers create better software (among other things).