I'm interested in both single coder and team competitions.
ACM [1] is a fantastic competition. The limited resources (teams of three, with one computer) force a premium on teamwork and working efficiently.
Many universities approach the ACM competition thinking that individual brilliance matters most. They spend months drilling their competitors with problem-solving skills, only to have it all fall apart on the day. Teamwork and discipline is what distinguishes the top teams and that's great experience when working in the "real world" too.
(disclaimer: my team won the ACM a long, long time ago. We were good coders, but so was everyone else in the finals. Our teamwork was shit-hot, though, and that made all the difference.)
[1] http://cm2prod.baylor.edu/login.jsfACM [1] has a big competition, brings in a lot of colleges and the like. Interestingly enough the format there is a set of problems to solve, as opposed to just one.
[1] http://acm.ashland.edu/The International Obfuscated C Code Contest [1]. The goals of the competition are as follows (from their website):
[1] http://www.ioccc.org/To write the most Obscure/Obfuscated C program under the rules below. To show the importance of programming style, in an ironic way. To stress C compilers with unusual code. To illustrate some of the subtleties of the C language. To provide a safe forum for poor C code. :-)
Game programming competitions:
All of the sites I list below are ongoing and have computer judging. That is, your entries are compiled, run, and scored automatically, then compared to all the previous submissions.
The Sphere Online Judge [1] has a wide variety of problems and supports a ridiculously large set of programming languages (dozens, from C to Whitespace).
Code Golf [2] is an all-golf site that supports some popular golf languages (Perl, PHP, Python, Ruby).
The Online Judge [3] at Universidad de Valladolid hosts a lot of ACM problems, with support for the ACM languages (C, Java, C++, Pascal)
[1] http://www.spoj.pl/[1] http://www.codechef.com/CodeChef [1] is a global programming community. We host contests, trainings and events for programmers around the world. Our goal is to provide a platform for programmers everywhere to meet, compete, and have fun. CodeChef is a noncommercial organization operated by Directi, an Indian software company based in Mumbai, India.
Not a classic competition, but if you like programming games: Robot Battle [1] or AT-Robots [2] (both have competitions, too).
( Wikipedia [3] has a nice list of programming games...)
[1] http://www.robotbattle.com/The Underhanded C Contest [1] -- it's like IOCCC [2] with a purpose :)
[1] http://underhanded.xcott.com/The Algorithmist [1] has a list of Online Judges with Problemsets and Programming Contests. It also has a calendar [2] of upcoming and current contests.
[1] http://www.algorithmist.com/index.php/List_of_ProblemsetsIEEE Xtreme Programming Competition [1] should also be mentioned. It is an annual 24h programming competition for IEEE student members. 970 teams have registered for the competition in 2010.
[1] http://ieee.org/xtremeCheckout http://www.bitwise.iitkgp.ernet.in/register
This is one of the top ranking engineering schools in India. Sponsors include Google and others.
TopCoder is nothing more than a way for companies to pay a fraction of development costs by getting a bunch of devs to work on a project in guise as a contest were only one or two will get anything. The rest are screwed since they worked for nothing and the innovation created by some will be outright stolen with no compensation. At best, a 'topcoder' winner will get a fraction of what he or she should be making for the work. eg 5k job, bunch of devs working, all the ideas used by the company and the 'winner' gets 1k. It's nothing more than a way for companies to exploit hard working and talented developers.
Railsrumble I did that this year, lots of fun. 48 hour contest.
CoderByte [1] is a pretty cool place to start developing quickly and participating in competitions.
[1] http://coderbyte.comDWITE [1] is a high school level competition if you want that level.
ACM-ICPC [2] is a pretty big deal if you want a college level competition.
[1] http://dwite.ca/If you're into MATLAB, the MathWorks has a bi-annual competition [1]. No big prizes, just bragging rights. It has a unique structure where, at certain points in the week-long competition, everyone can see (and thus use and modify) the code submitted by everyone else.
[1] http://www.mathworks.com/contest/armyants/about.htmlIf you like Mathematics and programming, have a good look at MCM. It is about mathematical modeling, where you need to program.
Data mining competitions [1] at TunedIT. A bioinformatics contest is organized right now.
[1] http://tunedit.org/challengesPaypal X [1] has a developer challenge just starting. They claim to have a grand prize award of $100k
[1] https://www.x.com/community/ppx/devchallengeWe just started a new one. The Windward International Collegiate Programming Championships [1] is a code war between most of the top computer science schools. I created this because my daughter, who goes to Harvey Mudd, asked me to set up one there. It was so much work creating the programming challenge I figured I should ask other schools if they wanted to participate. And boy did it snowball.
Anyways, should be a really fun time for all involved. And if most like it, we'll do it again next year.
[1] http://www.windward.net/Windward_International_Collegiate_Programming_Championships.php