I’m utilizing reCAPTCHA to stop comment and/or email spam by “reading books”. (If you don’t know what a CAPTCHA is, their website explains it comprehensively.) Installing the plugin and getting the API keys were simple.
The book pages are being photographically scanned, and then, to make them searchable, transformed into text using “Optical Character Recognition” (OCR). The transformation into text is useful because scanning a book produces images, which are difficult to store on small devices, expensive to download, and cannot be searched. The problem is that OCR is not perfect.
reCAPTCHA improves the process of digitizing books by sending words that cannot be read by computers to the Web in the form of CAPTCHAs for humans to decipher. More specifically, each word that cannot be read correctly by OCR is placed on an image and used as a CAPTCHA. This is possible because most OCR programs alert you when a word cannot be read correctly.
This seems like a win/win situation, right? So why don’t more websites (i.e. blogs) utilize this service?
All Narfed Up 
My only issue with Captcha (and moreso reCaptcha) is the fact that it’s sometimes difficult to actually see what the words are, requiring numerous attempts more and more frustrating.
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I’ve been using an Akismet and Spam Karma combination and it works great.
I’m not a big fan of any extra for the commenter.
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@Chris: I’ve since disabled it because of that fact.
@Nick: I’ve gone the more minimalistic route, too.
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FAN-tacular. Although I should apologize for my piss poor grammar with my earlier comment. My bad.
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How well did reCAPTCHA work while you had it installed? Honestly, I hate captchas too, but I’ll be going on a bit of an extended vacation soon and am thinking about adding this as an extra layer of protection while I’m gone. At least it’ll contribute to a good cause too, right?
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@James: I think it worked well. Nothing really comes through anyway, since I don’t get too much traffic. 😉
Wherever you’re going for vacation, have a great time!
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In that case, I think I’ll use it while I’m away. As for the vacation, I’m sure that I’ll enjoy it. Thanks!
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I think that you should do like what ubuntuforums.org does. Before you post there, you are asked a random question such as, “How many ears does the average human have?” That is such a simpler way to filter out spam and such.
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