Some kind of anonymous gateway might be fairly cool but the problem is anonymity is a double edged sword. Just ask (name escapes me), an old anonymous email service that got shutdown because of abuse (I want to say anonnet.fi but that's incorrect)
anon.penet.fi? They shut down in 1996 after the Cult of $cientology alleged that someone had used them to email their "secrets."
That's the one (and the correct reason). Slightly different risk but basically the same problem overall.