I've given up on the visual captchas. I hit my limit on Rapidshare with those stupid cats that looked exactly like the dogs.
I just hit the audio button now and get it on the first try.
+1 for pretend blindness!
I think a better captcha would simply be a semantic one that had a mathematical answer, like "If Jane was born in ninteneen eighty two, how old was she in two thousand and five?" and you'd answer "23".
The brighter side is that it would also keep morons out.