As far as CAPTCHA’s go, I think that the one that Digg.com uses for story submissions is fairly reasonable. It’s monochrome, decent contrast, and doesn’t try and get too fancy with out of focus characters or exotic fonts. Of course I have a preference for my own PuzzCAPTCHA as far as usability goes, but for mainstream CAPTCHA’s I think Digg’s in intelligently done.
Maybe a little too intelligently, actually. I think that it might be trying to send me messages. I logged in to submit a story, and was wondering (naturally) whether or not it would go hot. At the last step I was presented with this almost prophetic message from Digg, seeming to tell me exactly what the chances of the story hitting the front page actually were:
So, what exactly is it that you are trying to tell me here, Digg? 😀