Well I have a day off so I have been searching the web for something to do and I found this really cool contest. Basically how it works is a really really difficult problem is posted (bi-)annually and participants submit their best results, the winner gets a really weird voucher, but probably the best prize is the bragging rights.
Please note: According to the site the only information that may not be shared between participants is code and solutions. So you are free to discuss algorithms and methods for solving.
Have fun my demented friends...
EDIT: I just realized I made a stupid mistake in the title, lol