From the Kickstarter blurb: “A spectrometer may not sound like what you wanted for your birthday, but it’s a ubiquitous tool for scientists to identify unknown materials”
The open hardware kit is just $35 or you could make your own from a piece of a DVD-R, black paper, a VHS box, and an HD USB webcam.
via Public Lab DIY Spectrometry Kit by Jeffrey Yoo Warren – Kickstarter.