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
The perk basically 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. Essentially, this perk is very useful by allowing you to use more common items to repair other, more uncommon items.

Many consider the greatest asset of this perk to be the ability to repair and maintain rare and hard to obtain items using simple mundane ones. Ranger Veteran Armor can be repaired using any medium-class armor, and guns that use similar ammunition types can repair each other (such as the Assault Carbine and the Light Machine Gun). However some weapons can be repaired beyond just their own gun and ammo type, hunting rifles for instance, can be used to repair lever-action shotguns and hunting shotguns. Another benefit is that lots of money can be made by buying cheap weapons and using them to repair and sell worn-out but expensive weapons (ie using a Varmint Rifle to repair a Hunting Rifle).

Word of warning though, that once this perk is taken, unique and modded weapons WILL show up on your repair screen just like they did in Fallout 3, since these unique (or modded) items are nonetheless in the same category as their base items. As such, you are advised to be cautious as to what you're trying to repair, with which item as ingredient.

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, clothings can be used to repair each other within their category (Light, Medium, Heavy). Headwears are even less restricted; entire headwears - including apparels like eyeglasses - can be used to repair each other.

Guns are not strictly categorized by similarity, but by price. For example, a 12.7mm submachine gun cannot be repaired by other submachine guns, but by sniper rifles, automatic weapons and carbines. A short list of items that can be repaired with other, similar items, includes, but is not limited to:

Weapons:

Ripper - Hatchet, combat knife, lead pipe, police baton, knife, switch blade straight razor (One handed melee)

Chainsaw - Baseball Bat, golf club, rebar club, shovel (Two handed melee)

Laser RCW - Plasma Rifle (Energy Weapons)

Plasma Defender - Laser Pistol (Energy Weapons)

Plasma Caster; Incinerator; Flamer

Ranger Sequoia - .357 Magnum Revolver (One handed guns)

9mm pistol; 9mm Submachine Gun; 10mm pistol; .357 Magnum Revolver; .44 Magnum Revolver; Weathered 10mm pistol; 10mm Submachine gun; Maria; Ranger Sequoia; Sawed-off Shotgun; Silenced .22 Pistol

12.7mm Submachine Gun; All-American; Assault Carbine; Gobi Campaign Scout Rifle; Riot Shotgun; Service Rifle; Silenced .22 SMG; Sniper Rifle

Anti-Material Rifle; Brush Gun; Caravan Shotgun; Cowboy Repeater; Hunting Shotgun; Hunting Rifle; Lever-action Shotgun; Single Shotgun; Trail Carbine; Varmint Rifle

Sniper Rifle; Service rifle, Silenced .22 SMG.

However

A Grenade Rifle can be repaired with a Minigun, but the reverse is not true; ie Minigun cannot be repaired with a grenade rifle. (This is a glitch that happens even without this perk.)

Armor:

Power Armor - Metal Armor (Heavy Armor)

Any headgear (T-51b Helmet, ect.) - Glasses (Headwear)