Do you know any websites with a good hidden challenge? I found a great one &would like to find more.?

Question

Through a fellow user known as Bill I discovered this site.

http://www.justinthyme.info/page7.html
and the book Justin Thyme.
Can't wait to get the book after doing the site.

The site poses the question "Who is the real Pananma Oxridge". Cryptic clues and anagrams and even some bianary sleuthing was reqiured to find the identity of the author. I was up till 2 in the morning solving the case. Loooovvvveeed it!

Does anyone know of more sites with great riddles to solve or good mysteries of some sort. I'd love to find another site similar to this or one just to challenge my brain and wake it up now and then.

I put the link to the puzzling clues page in my post. It's really probally better to start at the competition page if you go to the justin thyme site. Click the link at th ebottom of the page.

Answer 1

donniedarko.com

Answer 2

http://www.mensa.org/index0.php?page=12

Mensa questions... some of those can be challenging.