Jury Rigging

"You possess the amazing ability to repair any item using a roughly similar item. Fix a trail carbine with a hunting rifle, a plasma defender with a laser pistol, or even power armor with metal armor. How does it work? Nobody knows…except you."

- Explanation of perk from Vault-Tec

 is a perk in Fallout: New Vegas.

Effects
Yep, repair a chainsaw with a baseball bat...

The perk, available at level 14 or higher, allows you to repair items based on category instead of type. For example, you can repair the rare Ranger Sequoia with the common .357 magnum revolver. Same goes for armor and clothing as well.

So far, there are at least 10 categories of weapons that the perk will enable repairing each other within category; Unarmed, One handed melee, Two handed melee, small inexpensive guns, high-end guns, energy weapons, heavy weapons, explosive throwers. Likewise, clothing can be used to repair each other within their category (Light, Medium, Heavy). Headgear are even less restricted; entire headgear - including apparels like eyeglasses - can be used to repair each other.

Weapons are categorized, to some extent, by the method in which they fired. For example, an anti-materiel rifle can not be repaired by a sniper rifle, because the sniper rifle is not manually re-chambered. The anti-materiel rifle CAN be fixed by weapons such as the Hunting Rifle, since they fire in the same way. Some discrepancies arise with some other weapons though. The 12.7mm SMG is categorized as a two handed gun, and therefore can not be repaired by the 9mm and 10mm SMGs, since they are one handed guns. A (somewhat) complete list of all weapons that fall into specific categories follows.

Repair Categories
Each weapon and armor falls under a specific category in which all weapons/armors repair each other. If you find a weapon outside of (or not included in) a category here, feel free to fix/add it.

Unarmed
Boxing tape; Boxing gloves; Dog tag fist; Bladed gauntlet; brass knuckles; spiked knuckles; Mantis gauntlet; power fist; Zap glove; Displacer glove; Ballistic fist

One handed melee (blunt)
police baton; lead pipe; Ripper; Dress cane; Tire Iron.

One handed melee (blade)
straight razor; switchblade; knife; hatchet; combat knife; Machete; cleaver; Machete gladius; Shishkebab.

Two handed melee
baseball Bat; shovel; 9-iron; rebar club; sledge hammer; super sledge; Bumper sword; chainsaw; Thermic lance; Pool cue

Energy Pistols
laser pistol; plasma pistol; Plasma Defender; Recharger pistol; Pulse Gun; alien blaster.

Energy Rifles (Laser)
laser rifle; Tri-beam laser rifle. Recharger rifles can be repaired by Laser Rifles, but not the other way around.

Energy Rifles (Other)
plasma rifle; Laser RCW; Multiplas rifle; Recharger rifle; gauss rifle.

Energy Weapons (Heavy)
Plasma Caster; Incinerator; Heavy incinerator; flamer; Gatling laser

One handed guns
That Gun; 9mm pistol; 9mm SMG; 10mm pistol;10mm SMG; .357 Magnum Revolver; .44 Magnum Revolver; Silenced .22 Pistol; Sawed-off shotgun; 12.7mm pistol; Detonator.

Two handed guns
Service rifle; Assault carbine; Marksman carbine; sniper rifle; Riot shotgun; silenced .22 SMG; light machine gun; 12.7mm SMG.

Bolt / Lever action guns
BB gun; Varmint Rifle; Single Shotgun; Cowboy Repeater; Caravan shotgun; Hunting Rifle; Lever-action Shotgun; Trail Carbine; Hunting Shotgun; Brush gun; Anti-materiel rifle; This Machine

Heavy Guns
Minigun

Launchers
Grenade rifle; grenade launcher; Grenade machinegun; missile launcher; Fat Man.

Heavy armor
All Heavy armors. Power armor, Metal armor, etc.

Medium armor
All Medium armors. Combat armor, NCR armor, etc.

Light armor
All light armors. Leather armor; wasteland outfit; etc.

Headgear
All head items. T-51b Helmet, Glasses, ect.