Pilot Light (Fallout 3)

The pilot light is a miscellaneous item in Fallout 3 and Fallout: New Vegas.

Uses
In Fallout 3, one is needed in the creation of a Shishkebab. In Fallout: New Vegas with the Dead Money add-on installed, one is required to craft a gas bomb and the Cosmic knife super-heated.

Fallout 3
They're frequently found in ovens (found in many abandoned houses, for instance in Minefield), or in workshops. A pilot light can be obtained early in the game by searching through Silver's stove inside her house in Springvale, in the Super-Duper Mart in the back room, or in the RobCo facility.

Fallout: New Vegas
Similar to Fallout 3, pilot lights in Fallout: New Vegas can be found in ovens. Many can be found in the basement of the REPCONN test site, especially in the storage room in the south-west. There are also several of them lying on the floor across the whole basement.
 * Seven can be found in Novac near the gas station, on top of the shelves
 * 5 in the train tunnel
 * 4 in the Gomorrah suites
 * 4 in Cerulean Robotics
 * 3 in Zapp's Neon Signs
 * One can be found in a Nelson house
 * Novac, in Jeannie May Crawford's house, in the oven
 * One can be found in oven at Fields' shack
 * In an oven inside a Goodsprings home
 * Can be found in the ovens in the Lucky 38 presidential suite.