Redairu Nanashii's Ultimate Attack.

The Annihilator Beam, code-name the A-Beam. Harnesses the electromagnetic field of the Earth and all electricity in the area, including generator and air alike, and channels it into a wave of energy that sweeps a target range, from only a few feet wide, to thousands of miles, lasting for as short or as long as desired. The effects of the A-Beam are as such: All mechanical weapons and computer systems, including vehicles on ground and in the air, cease to function, and will forever cease to function. The effects are a devestating blow to the enemy's firepower and economy, forcing them to build from the ground up if ever they wish to attack again.

It's a sad excuse for a post, but at least it's something.