Developer work metrics tool?

Is there some tool to measure developers work, not only by lines of code the produce/reduce(which is kind of misleading) but perhaps possible to tap into trac/redmine etc and see how many bugs are closed etc.

It should only be used as a fun motivator to finish things off and really get things done. Perhaps some sort of competition could be arranged as well.

If it didnt include any specifics it could be made public, even for non-public projects. Would be enough to see that developer x closed y bugs this week or so. Of course hard to compare this between projects, but would be fun to see how work progresses for past collegues and within teams as well.

Anything like this available? Or is it worth pursuing? :)