Further to my earlier post about associating fund raising targets with specific goals, it might be handy if we had a general ball park figure to aim to.
If we had a rough idea how much money is needed to finish this project I imagine it would push some people along much more than incentives like offering props as prizes (not that the prizes are a bad idea in of themselves).
You could use a graphic display for how close you are to getting the necessary funds.
For example if this were ANH:R you could have had the tractor beam power gauge or the targeting computer from the trench run.
I'm not sure how that would translate into an ESB:Rometer (maybe it could be the AT-AT's getting closer to the Rebel generator).