DIY spectroscopy
From Hackteria Wiki
http://www.rsc.org/Education/EiC/issues/2007Sept/BuildYourOwnSpectrophotometer.asp
http://www.dusseiller.ch/labs/?p=630
http://publiclaboratory.org/tool/spectrometer
from hostprods:
http://hostdev.wordpress.com/2010/03/02/further-adventures-in-spectroscopy/
Here's some links to a few opensource meditations on this issue.
http://www.instructables.com/id/A-simple-DIY-spectrophotometer/
http://www.creative-technology.net/MAKE.html
http://openwetware.org/wiki/Citizen_Science/Open_Spectrophotometer_Pr...
http://blog.makezine.com/archive/2008/11/safety-spectrometer.html
http://sci-toys.com/scitoys/scitoys/light/spectrograph/spectrograph.html