One day I had an epiphany. I realized as I was programming at my computer that nobody had a freaking clue what I was actually working on. If someone asks how their low-priority project is going, I just say that I'm still working on it. They have no way of knowing if I'm actually working on it right now. In the real world, saying "no" a lot will get you enemies. It's much more diplomatic to only work on some low-priority project an hour or two a day (you don't have to tell them your are only spending an hour or two a day), or say you'll get to their project immediately after you finish this thing your are working on (which can be a small component of your large important project). It's important to know how to say "no", but in practice it is important to minimize the number of times you say "no".