> If you're hosting 50 sites on the same IP address, and have actually managed to get them to profitability, and Google bans the IP, now what?

You tar the sites and move them. It typically isn't that difficult, however most of the people who run the "online niche" strategy have got little technical know-how, so if you can do this stuff you're ahead of the curve.

It's even better if you know a programming language because you can create tools that handle the dull repetitive tasks (eg, backlinking) that you need for it to work at scale.