Greying Japan has a new weapon to scare people into saving for their retirement -- an exploding piggy bank.

The "Savings Bomb," which goes on sale in Japan next week, "explodes" and scatters coins if users fail to save for a long time, toy manufacturer TOMY Co Ltd said Thursday.

The battery-powered toy -- designed as a cartoon-style, ball-shaped black bomb with a skull and crossbones logo -- lights up, makes a noise, shakes violently and scatters coins if it is not topped up for a long time.

"Users must pick up and collect the scattered coins and reflect on their laziness," the Japanese company said.