NeoThermic wrote: Just a small point, asking math questions isn't a good idea. A lazy bot writer doesn't have to parse much bar a google result page:
http://www.google.com/search?q=What%27s ... nus%201%3F" target="_blank
With a bit of programming, I'm very sure most of the questions you've put in as samples could be googled by a bot.
Secondly, the system suffers the flaw that is constant in all situations: the forum admin.
If the code ships without stock questions, few admins are going to take the time to add questions/answers to the system. If the code ships with some default questions, many admins will just use those, and since plain text on a page can be parsed as plain text, it won't take more than 30 seconds of programming to wirte a bot to read and lookup the answer.
The math thing was just an example. I forgot about google solving simple math problems, but if a bot searches for simple word problems, how will it know which word(s) the answer is?
I also mentioned before that there shouldn't be a standard set of questions, it should be filled out by everyone who wants to use it. If not a replacement, I think it's a good alternative to the current system.