mk1004 writes: Yahoo news has an article explaining how the text-based CAPTCHA is giving way to ad-based challenge/response. It's claimed that users are faster at responding to familiar logos, shortening the amount of time they spend proving that they are human.
I've never been canoeing before, but I imagine there must be just a few
simple heuristics you have to remember...
Yes, don't fall out, and don't hit rocks.