I used to be an exception too. With so many kids at home and they keep me so busy I can only work on one project at a time. I don't buy but just enough to make the project plus a tad more for when I miscut (notice, that is not an if I mess up, but a when I mess up). I have no stash, though I did get a nice piece in the mail for my birthday.
I am, for the very first time, working on 2 projects at once. I have a top I'm making for my Army-stepson that just wen to Iraq. I'm also doing my first Mystery quilt. Since the pieces only come out once every 2 weeks, I have time to get them done and then too much time on my hands.