depends entirely where you live and what website you run
theoretically you can hide the ownership of a website pretty easily, assuming it's not a site cathering to local surfers
nevertheles, this still leaves the question of how you want to run the business and receive the money, without it being seen by the taxman
and even if you accomplish that, then you can't just be unemployed and spending money on cars and houses, you need a source for your money, before you can spend it on bigger things
so the best idea is to get legit and pay the taxes
