As a result of feud between neighbors in 1976 there was the invention of “vacuum Cleaner in reverse.” To spite your ex PAL, a resident of Tokyo, Junnosuke Mihara inserted into a compact device the bag of dust, which flew and exploded in the air. Eventually, Mihara built in camera timer and optical targeting system on the enemy. The author of the idea, which has been repeatedly arrested for violation of public order, sincerely believed that the invention can be useful in local wars.