Living in tight-packed central Tokyo, it can be a real challenge to get laundry dry - there are just too many Metropolis-style skyscrapers blocking the light, plus the lengthy rainy season from May or June makes things even harder. That's why Asahi Kasei Electronics has come up with a rain alarm to help frustrated citizens.

The company's Rainfall Sensor AAM-100 sells for just ¥3,980 (£17) and uses wireless technology to help city dwellers keep a weather eye on the world outside. The idea is that the detector/transmitter part of the sunflower-styled pairing is placed outside on a balcony or porch, while the alarm/receiver sits indoors waiting for the call.

The rest is pretty simple - when rain or snow falls on the detector, radio-frequency signals set off the alarm inside, encouraging some rapid Pavlovian laundry retrieval. The gadget might seem like an unnecessary luxury, but buildings in Japan can be so tightly packed it's easy to overlook what's happening outside, so help can be welcome.

Although Asahi Kasei has no product page yet, you can check out Plastic Bamboo 's video of the device in action with a wet finger substituting for rain over on YouTube.