Advanced email spam filtering

Hi,

My spam situation on my current email account has been getting gradually worse over the past few months and now it is just getting beyond a joke. For every real email that i get i'll get at least 5 spam messages.

After trying to send someone an email a few months ago i received this email in my inbox.

Hey, I receive a whole lot of spam, and in an effort to stop the endless alerts of new emails, which are 98% spam, I have setup this stupid, annoying, automated system (BoxTrapper). Here's the deal: I'm not going to receive your email until you respond to this thing. Isn't that super? You'll only have to do it once (for this email address). All I ask is that you respond to this message just this one time. Don't mess with the subject line, please. You can write whatever you want in the body. In fact, you don't have to write anything at all. Just respond, subject intact. Thanks

Something like this would be the perfect solution to my growing problem however i have done some research on "BoxTrapper" and it looks like you can only use it if is already pre-installed on your email server by your web host.

Does anyone know where i can find a similar service? Any help is much appreciated.

Thanks in advance,
Jon