There is a new law going in effect tommorow, July 1st that effects anyone in the US doing mailing or anyone with a business presence in the US. (If you don't follow CAN SPAM then don't even bother reading this

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Basically the law sets up a "Do not E-mail" registry for kids. If you mail prohibited content to anyone on the list you are going to jail/getting sued.
This is what MarketingSherpa says qualifies:
o Obvious stuff -- porn, gambling, pharmaceutical offers, phishing, Nigerian scams, alcohol, tobacco, etc.
o Less obvious stuff -- financial services (credit card, banking, and mortgage offers), automotive marketing, dating and matchmaking services, etc.
Read the whole thing over at
MarketingSherpa