Some of the best projects I have worked on have been those with momentum. It may be just a feeling, but regardless of whether the project is on schedule or behind, when everybody is on the same page productivity starts to breed productivity and a little more seems to get done each day.
I wonder if it would be possible to formalize this feeling into something that can be modeled, measured, reported and ultimately used to bring transparency to software projects. I started an open source project on github.com today to play around with this idea. Check it out!