[antialiasis]

Phew, I haven't been on for a while.

Whoever asked for a feature to allow people to put images as the question: all you need to do is insert the HTML for an image as the question, as HTML will be parsed.

Everybody who has it installed and working but is still getting spam, I'm afraid this hack is logically 100% bot-proof until the day they create bots with flawless human intelligence, so if spammers are getting through, they are clearly human and impossible to stop with any sort of anti-spam system. (You could, of course, try to make more difficult questions - if, for example, all your questions are simple math problems, it is quite possible for bots to be programmed to pick up the numbers and mathematical operations from the string of text and enter the answer in a field, while if you ask random common-sense questions (and especially, if you own a specialized forum, answers that require some knowledge in a particular field that true members would have), they will be impossible for a bot to crack, and if they're difficult enough they might stop human spammers in their tracks as well, as they will not bother with spending time trying to Google the answer to the questions or something just to register at one forum.

The reason it is bot-proof (at least with decent questions) is that the answers to the questions are stored only on the server. From what I could understand of that other hack that will present the user with a choice of images, it offers very weak protection since the answer is in the filename of the image and all a bot programmer would need to do is be aware of this fact and make the bot extract the answer from the page when it is presented with the question. Here, there is no way to just retrieve the answer; it is all stored in the database, which the bot can't access, and the answer is never within the reach of anybody who does not actually know the answer to the question. Since bots do not have the artificial intelligence to be able to read a question, understand it and have the knowledge to answer it in more than some extremely limited cases (like the math questions mentioned above), it is impossible for them to get around it.