Now, I've only been a project manager once, so I definitely have no idea what I'm talking about. But two principles occurred to me while I was procrastinating a paper I had to write. They are quite along the same lines as -Ofun, but a little bit more specific:
* Always make people feel like they're making a difference.
* Never make people feel like they're making "the final product".
And the reasoning is: #1 makes them start, #2 makes them finish. Nobody ever finishes "the final product", because it's never quite designed well enough, or quite as flexible, or quite as orthogonal, etc. as they'd like it to be. And of course, before you start writing "the final product", you have to have it all worked out in your head. These emotional responses are extremely counter-XP, and never end up working, of course. So #2 is basically there to shatter those false emotions and get people into XP mode without overengineering.
I'd be interested in hearing from some people with management experience on these thoughts.