This condition afflicts musicians and singers of all kinds, but seems to be especially virulent in electric guitar players. It is typified by an uncontrollable urge to buy, beg, borrow or steal the latest piece of musical equipment seen in a store, in a magazine, on TV or on another musician.
Poverty is the only known prevention (and only known cure) for the disease.
G.A.S. is the most likely explanation for any musician who possesses more than the required number of his/her chosen instrument (ie more than 1), but is more usually seen in the miriad unnecessary musical accessories hidden around the victim's room - such as amplifiers, electronic tuners, fold-back speakers, amp stands, gigantic speaker and PA stacks, guitar polish, guitar polishing cloths, several grades of strings, multiple gig bags full of things which buzz, click or glow in the dark, and, and, and....
While a gear whore can be described as someone who has the best, most expensive, coolest gear, and a damn lot of it; it is more commonly used to describe an individual who simply MUST have a shitload of gear, useful or not.
Military Lingo - A person who always wants the newest scope, site, rail system, or thing that they will never end up using. They will even spend money aquiring this shit knowing full well they will never use it. They are usually RANGER/SF wanna be's. These types are often seen rubing one off to a rangerjoe's magazine
Look at PFC Clark over there with his new M4 Pistol Grip. He is such a gear queer!