Has anyone made one of these DIY spectrometers, using a webcam and a DVD-R disc:
http://publiclab.org/wiki/spectrometer
I guess the light gathering power of a webcam might be too low to get much of a spectrum through a telescope from anything but the very brightest targets (like the sun, through a solar filter)?
Anyway, for a total outlay of approximately $0 (I have several old webcams and DVD-R discs that I am prepared to sacrifice in the name of science!), it could be fun even to use for daylight handheld spectral analysis.