Relentlessly Profitable- how great ideas kill companies
spreadsong.com
spreadsong.com
If money is coming in at the end of the month you're on the right track, if not then you won't be around for long.
Admittedly, we're scratching an itch, and very focused on the idea of 'getting money by making our customers really, really happy.', so the idea of 'changing the world' is really way down on the list. Even so, I'm expecting a very, very interesting ride. :)
For example, Google and Amazon were definitely idea companies. Neither made any money -- and, in Google's case, wasn't even sure about how they'd make money -- for quite some time. But, both have seem to have done acceptably well.
Granted yes I'm very much with the rest of the HN community that we should concentrate on making products and all.