Made entirely from Japanese brown rice and salt, the Survival Senbei iPhone 5 case is intended not to protect your phone, but to keep you going in the event of a large-scale natural disaster.

A hungry inventor in Japan has invented an edible iPhone case. The product is “made entirely from Japanese brown rice and salt, baked into a crispy golden-brown senbei rice cracker that fits ...

It sounds bonkers, but that's the idea behind the world's first edible phone case, the £30 Survival Senbei, a fragile Japanese biscuit intended to be eaten in an emergency.

Kaki no Tane rice cracker and peanut ... Of course, the bag also shows off the ratio, in this case 10:0. Image: Kameda Seika Co., Ltd. Each pack of 6 bags weighs 150 grams and will cost around 183 yen ...

You can, however, easily make rice flour out of white or brown raw grains of rice by simply blending them at high speed for 30 seconds or more in a high-powered blender, like this Vitamix.