Creating a High School Programming Competition?

goatmon asks: "A few high school computer teachers across Tennessee have organized an annual "Geek Games" competition. We started last year with a great competition in PC repair, patterned after the VICA competition. This year we are trying to expand to add a competition in computer programming. The question is, how do you create a language-independent computer programming competition? Is it fair to have a timed test if one group of kids is hacking in Python and the other in C++? And who wins, the one with the shortest code, the fastest programmer, the one with code that works? Can anyone offer insight from experience or a pattern that we might be able to follow?"