Shishkebab

The Shishkebab is a melee weapon in Fallout 3, Fallout: New Vegas, Fallout 4 and Fallout 76.

Junk Shishkebab
The Shishkebab is a makeshift "flaming sword" that requires the appropriate schematics to build. The motorcycle gas tank provides a reservoir of fuel, the handbrake becomes the hand guard and the lawn mower blade becomes the blade of the sword.

Wakizashi Shishkebab
Unlike the Shishkebab in the Capital and Mojave Wastelands, the model in the Commonwealth and Appalachia is a far less makeshift weapon. Rather than a lawnmower blade and motorcycle parts meshed together to form the weapon, it is built around what appears to be a wakizashi-style sword with a proper hilt. The reservoir of fuel is shifted from a motorcycle gas tank worn as a backpack to a small tank on the blunt edge of the blade, with a series of pipes attaching to emitters along the edge of the blade. Below a second tank appears to power the pilot light that ignites the expelled gas. The pilot light is triggered by what appears to be the sole shared element between the two designs, a motorcycle handbrake attached to the hilt.

Gehenna
Gehenna is a melee weapon added with the Fallout: New Vegas add-on Gun Runners' Arsenal. In comparison to the standard Shishkebab, Gehenna has a brighter flame, different valve, handle and the motorcycle gas tank is more rusted.

Pincho moruno Шиш-кебаб 烤肉刀