As outlined by xkcd's recent alt text, this site downloads the top answers from StackOverflow for the tags "javascript" and "sort". It grabs the last code block in the answer (in theory, the "final" example), and tries to determine which function should be called. It proceeds to eval the code from StackOverflow, with the inputted data as the first parameter for the function.

If it returns a wrongly-sorted list (or you just want to keep playing), a link to "Try the next answer" will appear under the result.

You can view the code on GitHub. If you see any bugs (or just want to berate me), please file an issue.