I mentioned this in another thread, but this one seems to be getting more traffic, so I'll mention it here too. Why not make new and low stats accounts deposit BTC before they can send messages? I understand the need to allow buyers to contact vendors before a purchase, but really if they are serious about making a purchase, they should have BTC on hand to deposit into their accounts. Make it a minimum of 1 BTC before messages can be sent. For accounts with less than 10 transactions and $500 in purchases, there would be a 3 day delay on withdrawals, so the spammer can't deposit BTC, spam a whole bunch, and immediately withdraw the BTC. It would give admins the time to identify the spam accounts and delete them, keeping the BTC of course, and making the spamming not worth it. Accounts with more than 10 transactions and $500 would not have to deposit BTC to send messages and could withdraw immediately. None of this would apply to vendor accounts of course. Also, even when they deposit BTC, why not limit them to 10 messages a day or something? Is there really a need to send more messages than that for a new buyer?