No gas bill this month!
We've always kept our heat pretty low (67 during the day, 60 at night), but I've been especially good this year about turning it down when we go out. I also used foam tape in a few new places this year.
So I went online today to pay the gas bill, only to find that there wasn't one. We have balanced billing, and this is the month they even things out. Well, we lowered our gas usage enough that there was no bill at all this month!
I'll bet there are even more places where I can insulate or cut usage somehow, and now I'm inspired!