> My favorite CAPTCHA is the one on the Arch Linux forms but I realize this cant be used many places. > What is the output of "date -u +%V$(uname)|sha1sum|sed 's/\W//g'"?

> Easy to do but hard to do with computers. My second favorite are the math problems one.

> However if these become popular people will just write bots for them and were back to square 1.

Interesting...I wonder if they show destructive commands below a certain threshold. It would be funny if a captcha caused a bot to delete itself.