The Samophlange is a goblin-made component and a running gag in Warcraft.
The Samophlange was first mentioned in Warcraft Adventures by Gazlowe when Thrall almost steps on it. It is apparently very delicate. In Gazlowe's words, it is a revolutionary tool that is essentially a high powered drill designed to attach the snabgasket to the bleemseal's intake valves (both are zeppelin components). It attaches to a hose of some kind.
In World of Warcraft, Sputtervalve finds that the Venture Company (presumably Tinkerer Sniggles) is experimenting with something called a Samophlange, and sends adventurers to retrieve it from its Control Console. The says that it is used to "automatically regulate the flow of fuels, gasses, liquids, and related machinery". When retrieved, Sputtervalve breaks it, prompting additional endeavors (in Cataclysm even more so). Boss Copperplug seems to have invented it. Every goblin seems to be impressed with it at various stages, despite not quite knowing what it does.
This section concerns content exclusive to Cataclysm.
The Samophlange, or rather, an upgraded Induction Samophlange (which is very different to a trained eye), makes an appearance during the Twilight Highland's prequests in Bilgewater Port held by Smoot, who built it. It has become an object of reverence. Later in the Twilight Highlands the Samophalange falls into Alliance control and needs to be recovered again. After being recovered the Samophalange it is given to Captain Krazz.
The blasted Samophlange, keeping one's foot off of it, and not knowing what one is, originated in an infamous ThunderCats outtake. It can be listened to here. This outtake is referenced in the 2011 reboot.