Recruiting Humans with HTTP Headers

That's the key measure. To be honest, this is such an old technique that it doesn't seem especially cool or interesting. We've found writing good blog content and working on open source to be effective at finding good people.

http://www.humanheaders.org/ and https://github.com/randomdrake/human-headers/

randomdrake actually built a few browser extensions that will read out the headers and show them to you if they exist, which is pretty cool.

http://higg.im/humans.txt

Mine is nothing special, just a simple quote. There is even a whole site that crawls these files.

http://humanstxt.org/Standard.html

Some of them are gold. Get ready to see lots of ASCII art :)