I'm glad to invite you to my first short contest on codechef.com on Sunday, 20th. (Check your time zone here.) I should also note that Anton_Lunyov help my a lot in preparing of the contest, thanks to him.
In order to take part in the contest you should be registrated on the site, you don't need separate registration for the contest. The competition will consist of 5 problems for 2.5 hours, by the standard ACM-ICPC rules.
After the contest you can discuss problems here and public all your wishes for the next contests.