You can open up a cheap USB camera to get the nacked CCD sensor and put a radioactive source (Americium-241) from a smoke detector directly onto the chip. The

You can open up a cheap USB camera to get the nacked CCD sensor and put a radioactive source (Americium-241) from a smoke detector directly onto the chip. The CCD sensor, connected as USB camera, will record thousands of flashes/sec capturing the alpha radiation.