Marketing with Mike Volpe

Hire an intern to answer the spam. Have said intern follow all the steps right up to the point of commitment, then have them feign indecisiveness for 20 minutes before saying "no thanks." 
 
This way, the intern does "research", and you spam the spammer by taking up the spammer's time.

I like the response strategy that Drew Onstad came up with in Achewood: scam them right back.

Hi- it doesnt stop most of them, but I can assure you it annoys them terribly..I know it may get your ip flagged and all that, but in addition to posting the spammers real email (not the hidden one, usually looking through the code will help) on as many open forum sites as you can find (those that are clearly spam havens, in addition..you compose a huge email (in bytes- either by embedding images or mass (like a book) amounts of text or both..) the copy and paste their email addy into to box and the cc box (bcc too if you have it) many times..copy it in blocks and send them the same email over 800 times (the huge one of course) if it works well it blows up their inbox and fills it to capacity or locks it up..at the least, its a real pain to have to go through and delete all of those emails- if even once