I like the idea of having a big number to represent your "score."

Once I was on a team using Flyspray and one of our developers hacked it to display a real-time score. He had some convoluted algorithm that took into account percent completed, criticals, and priority. Everybody started working the number, trying to get it higher. It was great and become quite competitive. We'd even talk about our score with marketing and clients. The only problem followed a beta test when the client opened a ton of fixes. The number sank like stone. Not a big problem though. The developer tweaked his algorithm and bingo. . . our score was soon back where it belonged.