How to get rid of your CAPTCHA and still avoid spam
CAPTCHAs. You hate them, I hate them. Everyone's seen them and everyone will tell you they're annoying.
I'll admit, I used to use a Maths CAPTCHA, cause I thought it'd be easier for someone to add 5 + 6 than to read some scew text-characters. Apparently this only annoyed people more though (there is an amazing aversion to Mathematics out there). I can't blame you, it really is annoying.
And this one is very popular. Which apparently uses CAPTCHAs to help digitize books. That's great, but I don't feel like helping.
Which all brings me to something I'd encourage more people to use.
Spambots fill up fields in a form and submit. If there's a CAPTCHA, advanced spambots actually solve it and enter a value. Which leads to more advanced (nastier-looking) CAPTCHAs.
Invisible Defender is an example of spam-protection that does things a little differently. Instead of displaying a CAPTCHA, it adds a bunch of generic fields to the form. These fields remain invisible/hidden from the typical user:
(Most) Spambots don't realise this and fill up those fields too. The script detects if the fields were filled in and if they are, it shows an 403 error-page to the bots. I heard of this simple-concept about a year ago and thought it was such an eloquent solution. It almost seemed too simple to work.
Mind you, spambots are getting smarter, so some get past this too. But so far it's worked pretty well for me. I'm curious to know about your experiences too!