It's so small that it could easily be mistaken for a small pack of mints. In fact, if you actually have a packet of Frisk on you hang on to it, it'll come in handy.
Pocket Geiger, one of many gadgets on display at the Maker Faire Tokyo 2012 last weekend, is a handheld radiation detector developed by engineers and scientists belonging to "Radiation-watch.org" — a pro bono project aimed at making high-quality radiation monitoring easier, cheaper and more citizen-oriented.
Founder Yang Ishigaki said the device uses tiny PIN photodiodes, which are commonly used as light sensors for infrared remote-control devices but can also pick up Gamma-ray radiation.