Geiger counters measure radiation, and since the earthquake in Japan, they're getting harder to find. The devices are small - you can get them as a wrist watch, something that hangs off your belt, something you can hold. The New York Times talked with the president of a company that makes Geiger counters: "During a typical week, Mr. Iovine says, he may get an order for 20 Geiger counters from a local government followed by several weeks without any additional sales. But in the week after the Japan earthquake, he said he received close to 200 orders and was now sold out. Customers are now warned that it will take six to eight weeks to fill any orders."