Dutch landscape designers Elma van Boxel and Kristian Koreman of ZUS used crowd funding to build a pedestrian bridge in Rotterdam. They got funding to design a wooden bridge that cuts right through an office block. These two designers simply made some sketches, set up a website and then began selling their bridge idea over the net. Since products/services are given away on Kickstarter (kind of like a form of equity, or in return for a donation you will receive product X), the designers offered to engrave peoples names into the wooden planks to those who donated.
Anyways, if extreme projects like these can be created on Kickstarter then anything can be created and funded. The next time I have an idea, I think I will try to turn to crowdfunding. It is also a great way to guage the future success of a product. 