On the assumption that my stress level correlates fairly well with how much I have on my To Do list, I wrote a little script to graph that.
That's a graph of the length, in bytes, of my "next actions" list, for each automatic commit of the list into bzr.
"Next actions" are part of the Getting Things Done productivity system. I've been doing it for a couple of years now, with varying success.
It seems I get things done at about the same rate as new stuff comes in. That's not entirely surprising: I try to limit the incoming rate based on my actual performance.
Now, if only I could perform better. Smarter, not harder.