One of my clients spoke to me when I made their new website and said they get about 3000 spam emails a day. They are mainly the usual offering Viagra, Loans and the phishing which so many people get caught out by.
So I offered him a solution. The solution would involve setting the catch all to delete all the emails it receives and having an online for users to fill in which send the client the emails.
The email one in which spam bots would not be able to guess from using information on the site but not one which would be too complex for users to remember after receiving a reply off the client.
This system was implemented and worked fine until the spam bots attacked. In 3 months 180 spam emails were sent to the account via the contact form. Which in relation to the clients previous email account was nothing but its still 180 too many. To solve this problem I wrote a simple image verification script and I have now added validation to all fields to block out certain patterns which are known spam type emails.