Bomb on a Stick

What's more destructive than a Blade on a Stick and almost as simple?

An explosive device used in contact, rather than more common lobbed or planted varieties. If the user is not a kamikaze, the pole provides (barely) enough range to avoid being caught in the blast, while still allowing very direct "guidance". Thus, the answer is "Bomb on a Stick".

Subtrope of X on a Stick. See also: Ramming Always Works and Boom Stick.

Anime and Manga

 * One Piece has Don Krieg with his Great Battle Spear — a giant spear that releases an explosion when swung with sufficient force.

Literature

 * In Without Remorse, this trope is pulled off with a shotgun shell primed to explode on the end of a stick, which blows a lethal hole in the target's chest and has a cop later remark the uniqueness of the wound would wind up in a medical journal.

Tabletop Games

 * Warhammer 40,000
 * Ork "Tankbustas" use Tankhammer, which is a rokkit on a pole. Orks are lousy shots, but reasonably good in melee, almost fearless, and have a chance for approaching the target vehicle without being mowed down due to being numerous and tough. They become casualties on the attack however (does not necessarily mean all the way dead, but this puts even an Ork out of action). Not as good as plain rokkit spam, but it works.
 * Human Rough Riders attack tanks and heavily armored infantry with Hunting Lances, which are, indeed, bombs on a shaft (though thee are variants). Those are single-use, obviously, but the rider and mount survive and can go engage something less armored with laspistol or saber.
 * Spelljammer has Goblin ship Urchin, which is a closed shell covered with pole mines.

Video Games

 * Team Fortress 2 has it as one of Demoman weapons.

Real Life

 * Pole mines were actually used on ships in XIX century; they became obsolete once self-propelled torpedoes improved enough to actually hit things merely twenty times longer than a barn, while defensive artillery was souped up enough that approach to ramming range became unlikely. Not quite as crazy as it sounds: while against a flotilla in the open sea it would be very close to suicidal (a larger ship could blow such a vessel to bits in one good salvo, or a few gunboats could intercept rather reliably), taking out a lone raider and/or hit-and-run near the shore (where such boats can lurk behind islands and bluffs, while larger ships cannot maneuver freely) are much more favorable scenarios. Russian Navy after 1877 had mine carriers as a special ship class; fast small vessel between brander and torpedo boat. Lift the mine out of magazine, affix to the pole, move the pole forward in its guides, switch the galvanic fuse on, you have an explosive ram. A partially destroyed pole is easy to replace as well (if the boat itself didn't crash or get crippled in the attack, that is). Reloading is a long process, but how often you can make ramming runs, anyway?
 * A specific example of the above: the H. L. Hunley, the Confederate submarine which was the first combat submersible to sink an enemy warship, the USS Housatonic, which was part of the blockade of Charleston SC in 1864.  The Hunley was armed with a "spar torpedo" that consisted of an explosive mounted on the end of a spar extending from the front of the submarine.  The Hunley was sunk when the torpedo exploded before they could detach the spar after ramming it into the Housatonic's hull, and went down with its target.