How to recruit curious people, the automattic way

I was doing some feeds processing and needed to check their HTTP headers. Oh the surprise when I saw this line among the headers returned by blogs from wordpress.com:

X-hacker: If you're reading this, you should visit automattic.com/jobs and apply to join the fun, mention this header.

They aren't the first ones to find prospective employees this way (Google did something similar years ago, posting some kind of secret message in billboards, I think), but it's funny nevertheless.

And who doesn't secretly aspire to be a hacker? ;-)