Everyone knows and loves captchas, the mini turing tests that more and more blog and forums are employing to help curb spam comments. Some are merely annoying while others rely in images so distorted that it is difficult for even someone with perfect vision to decipher.

That is why I found this alternative interesting:

Asirra (Animal Species Image Recognition for Restricting Access) is a HIP that works by asking users to identify photographs of cats and dogs. This task difficult for computers, but our user studies have shown that people can accomplish it quickly and accurately. Many even think it's fun!

The amusing bit is that Asirra was partially inspired by Hot Captcha, where you have to pick the attractive people to get by. (That one keeps telling me I am a bot. I guess my beauty sensors are perpetually impaired as a result of being constantly bathed in the intense light that is The Queen.)