Here is 2 for you to solve, first one is called Peter Answer one of my friend introduce me to Peter Answer by telling me it can read my mind and hear the question and answer if I shout the it, I guess it isn't called Peter Answer Virtual Tarrot for nothing and yes it was able to guess what the correct answer to my question is, now go and see if you can figure out what Peter Answer's secret is :)
Another site that I was introduce too some years ago was a puzzle game called Petals Around the Rose the idea is the computer will roll five dice and ask you to guess the score for the roll. the score will always be zero or an even number. your mission is to work out how the computer calculates the score and become a Potentate of the Rose, it took me around 10 minutes to figure out how the puzzle works and about 5 to 6 tries, I was so frustrated by the fourth try :) by the way there is also a great story about Bill Gates and the Puzzle on the site, I think that's it for me today, what a slow day.
Peter Answer - www.peteranswers.com
Petals around the Rose - www.borrett.id.au/computing/petals-j.htm