I was reading my Google Alerts this morning and came across an interesting article about hypermilling: basically changing your driving habits to increase your fuel efficiency. Things like slowing down, accelerating and braking smoothly, planning your trips better can actually improve your gas mileage. It doesn't seem like it would make that much of a difference, but I've been trying it myself, and it really does. I used to be lucky if I got 320 miles on a tank of gas; now I'm up to 360 or higher. That's an extra day of driving (I have a long commute).
Anyway, if you're interested, you can read the article here.
I was looking for a picture to include in this post, and I found this one by searching "hypermilling". Apparently the creator of this picture doesn't believe in braking. I thought it was amusing.