Personally, while the whole starting a business idea seems pretty cool to me, it's just far too grand, far too difficult and far too expensive right now!
I'm 20, I want to go to my simple 9 to 5 job, tackle a really difficult challenge, maybe debug some Magento because that's where the real challenge is at my company, then maybe for the last couple of hours I'll work on some of our in house products to enjoy the freedom of custom development.
Then I'll go home, make something to eat (at a reasonable hour) and hopefully spend a great night cuddling with my girlfriend while we watch old movies on my laptop.
While being a billionaire business man is very enticing, right now, at this point in my life, all I want is to be happy, and working 80 hour weeks to risk it on a 3% chance to make it something amazing just isn't worth it for it.