Covering Up CIA Torture
Yet Another Reason Not to Gawk...

Charging People to Comment

This might seem like a whacky idea, so bear with me....

Today, after deleting a dozen-or-so pieces of comment spam, I had this thought: Could I contractually bind comment spammers into paying money for leaving comments?  After all, comment spam is placed as a free form of advertising. (Put aside the issue of whether the spammer would be judgment proof.  I just want to know if I could charge them for leaving spam.) 

Assuming I could craft language that would catch comment spammers (say, by noting that any comments left for a commercial purpose cost money), would such a contract be enforceable?