It's kind of inspiring. I don't know a ton about finance or trading algorithms, but I know a fair bit (I think) about math and CS, and because of RenTech I've formulating my own trading strategies (just paper trades). Thus far all I've been able to do is lose all my pretend money by trying to play options, but it's still fun to try.
Will I be successful and make billions? Almost certainly not, but it's an excuse to play with different types of math that I don't play with very often, but RenTech proved that you can beat the market by taking advantage mathematics.