Help identify Martian craters

Dan writes:

Have a few spare minutes? You can help identify craters on Mars!

"What is this site all about?

There are many scientific tasks that require human perception and common sense, but may not require a lot of scientific training. Identifying craters on Mars is something almost anyone can do, and classifying them by age is only a little harder.

>From November 2000 to September 2001, we ran an experiment that
>showed that public volunteers (clickworkers), many working for a
>few minutes here and there and others choosing work work longer,
>can do some routine science analysis that would normally be done
>by a scientist or graduate student working for months on end.

Link

Discuss

(Thanks, Dan!)