Need to detect radiation? We sure hope not -- but if you're looking for a straight-forward, altogether geeky geiger counter, the Libelium gang has your back. En route to the Tokyo Hackerspace as we speak (and believe us, they need it), the Radiation Sensor Board for Arduino is a low-cost alternative to existing devices. It's available now either with a compatible geiger tube for €95 ($135) or without for €65 ($50). Hit up the source link to get started, but not before peeping the thing in action after the break. Is there anything you can't do with Arduino?