When Kickstarter was still in it's infancy, I had a lengthy discussion with a friend of mine about the pros and cons of the system. I brought up the possibility of someone watching an underfunded Kickstarter page until it's just about to close, and dropping a large fake pledge that would bring them just a hair under the pledge, just to troll them with false hope. We agreed that this would never happen, for a lot of reasons.
That ended up turning into a discussion about large fake pledges, and whether or not it would be easy to screw a project over that way. We remained cautiously optimistic that such a thing wouldn't be a huge issue based on the nature of Kickstarter's community, but seeing the reality of the situation right here in my face makes me wonder if this has happened before on a smaller project. It's pretty screwed up, to say the least.