Facebook's self-underwritten IPO

Can individuals who are non-resident non-citizens buy (and more importantly, subsequently trade) individual stocks in companies governed by SEC rules without working through a brokerage house/operation? This isn't rhetorical; I'm not sure of the answer.

It seems like this proposed model - direct selling to individual investors located internationally - would be rife with the potential for money-laundering and fraud, and would get around most of the know-your-customer regulations that US financial institutions are required to follow.