Captcha or Tic-Tac-Toe?

I have a confession to make. I hate Captcha's!

Those stupid little images that are displayed to you during or after you register on a site, that display a set of almost completely unreadable letters and/or numbers. It simply infuriates me when I see them. I live and breathe the internet, but even I can't tell what I am supposed to be entering into the Captcha sometimes. Just imagine what it's like for non-technical types!

So today I stumbled across Xero, and it picqued my interest enough for me to signup for the free trial. I completed the short signup form, and immediately after I see this:

No obsure image with a bunch letters that you can't see. I just get to finish a game of Tic-Tac-Toe! As long as I click on the correct square to finish the line with crosses, I'm in and registered.

Now that I might have to steal. Genius!