Kickstarter is amazing. If you've yet to hear about it, it's a fundraising site for creative projects, and surprisingly, the interesting projects tend to fare quite well.
For example: Imagine you designed a trebuchet—coined the trebuchette—and you wanted to start a business selling laser-cut models. But among other things, you need a laser cutter, and those cost around $20K. You calculate costs, and determine that to execute a viable business plan (for being in the trebuchette-selling-racket), you'll need $48K.
Who's going to invest $48K in making toy trebuchets?
The web community—with the aid of the Kickstarter platform, of course. Not only did Evan Murphy and Michael Woods raise the $48K they asked for, they raised $96,248. They prototyped a "full snap-together trebuchet kit... a great classroom demonstration, learning toy, or addition to your office arsenal".
Check it out:
The Trebuchette is an open hardware project, meaning the plans are available as a common.svg file, free for anyone to download, as long as it's used appropriately under the Creative Commons Share Alike Non-Commercial Attribution license.
Don't have the means to make one, but interested in purchasing a kit? Visit Siege Toys to sign up for the mailing list.