Vienna Technical University, Austria presented a way to measure Alpha, Beta, Gamma particles with a regular webcam. The webcam sensor is shielded from visible light by a 5um-thick aluminium foil and a software is used to analyse the video stream for characteristic patterns:
The poster has been presented at SIGGRAPH 2012:
"GeigerCam: Measuring Radioactivity with Webcams"
Thomas Auzinger, Ralf Habel, Andreas Musilek, Dieter Hainz, Michael Wimmer