This is a lesson that was learned on Slashdot in 1999 already I think. A 'karma cap' makes perfect sense and the total karma wouldn't even have to be displayed to the user himself, to avoid karma whoring. What does it matter if someone has 1500 or 15000 karma? They've both proven to be contribute; maybe the one with the higher score just has more time, or a more popular opinion, or has been here longer.

In the same vain, it's not easy enough to lose karma. By being active here, you will in the end always have good karma, even if your contributions are bad; it's very rare to see comments with lower than -5 karma, but it's easy to get a +10 comment, even if it's nothing special (I mean I know I've had a lot of those...)

I quite like the 'karma average' actually. You can argue whether or not it works, but to me, the two highest signal posters (that come to my mind) are grellas and patio11.

They have averages of 26.23 and 18.93, respectively. This, to me, aligns with my expectation that their comments are high value, well thought, and usually worth reading.

Compared to my own measly karma average of 4.57, which is comprised, often, of throwaway remarks and dumb questions, I think it's a fair representation of a user's contribution.

The actual number itself, I agree, is all but meaningless.

A small comment since people are upvoting and I did a rather meaningful edit: I wrote 'it's too easy to lose karma', but I meant (as was elaborated on in the rest of the sentence) that it's too hard to lose karma.