Startups – race or marathon?

I just read this entry over at 37signals.com by David Heinemeier Hansson. Those who know me personally know that I’m really passionate about startups, I read about them, I want to work for one and that I’m fascinated by the way the startups work at a completely different level compared to the boring big companies.
In startup culture, its not uncommon to hear superhuman efforts, endless hours, thousands of lines of code in a few months, no social life which, when everything goes right, ends up with the company being bought for a few million or in some cases, going IPO.
The problem with that, at least for me is, if I’m going to pursue my ideas full time, I don’t have any other means of income, so this means I need to be able to work simultaneously on my ideas and the freelancing work that I do.
Reading something like this brings back a sense of calm to me, and I remind myself that this is not a 100 meter dash, its a marathon, and like David’s example about the Italian restaurant during startup school, I just want to be a small successful Italian restaurant for now, not a Sbarro, although hopefully I’ll end up like it.