Stopping Spammers !%&*$#!#!!!!!! Any ideas?

I just responded with a comment on the site feed, but my suggestion basically covered what you've put here. If people reach exceed the limit, you can check the mail, or perhaps you can lift/raise limits for people that request it - then you can check their history, see if they're established etc. That of course relies on you being able to individualise the settings for mail limits!

From what I understand, people that make spam bots have been able to get their bots to read Captcha for the most part. I have seen sites implementing random questions that give specific answers like "how do you spell green?" then of course you would type in green. Some not as easy as that.

As for the manual spammers, I think a way of limiting the number of e-mails sent would be very effective. Possibly offering a way for members to "validate" their account, to prove they aren't a spammer. I haven't checked the mail system out yet, so not sure if this is there.. Offering a way for members to report a message as being spam could help catch people as well. Most people on sites like this will usually report such mails if given a simple way to do so.

I like the idea darkcatalyt came up with. You could try something like "what is this shape?" and then an image of a square, circle, triangle, heart, so on, all random.