How long will it take you to write five JavaScript functions?
My time was 3 minutes, 9 seconds. I was held up in the last one because I couldn't remember off the top of my head how to identify an array. I was using the typeof operator instead of Object.prototype.toString :-)
Study on what makes a person "get" programming on a fundamental level. It suggests there are two types of people in the world: those who can program and those who can't.
Additional papers by the same author: http://www.eis.mdx.ac.uk/research/PhDArea/saeed/
If you have the administrative web site enabled on the WAN interface, then anyone can do anything just by setting a particular hardcoded User-Agent value in the HTTP headers.