I've only ever backed games from the series "The Banner Saga"
Turns out, not only did the first one come out and gave everything it promised, it was good and popular enough to spawn a sequel without crowdfunding that was even better. The third and final game was put on kickstarter and gained double what it set out for. And with Its creator "Stoic" giving us monthly updates, it's looking good for a release.
There have been so many scandals and daylight robberies on the site though, I can see why nobody would want to put their money towards something that will never come out.