When a person is scrawny and slight and has intensely long arms--arms big enough to hug you and 3 of your closest friends because of their length, they are said to have the "ganglies." It is also called having the "ganglies," when a person who has slender long arms waves them like a wacky inflatable arm flailing tube man from Family Guy.
Jim Carrey has the ganglies because he is 6'2" and his arms reach within an inch of the midpoint between knees and hips.
Michael Cera, too, has the ganglies because he is 5'9" and has arms that hit closer to his knees than his waist.
Any tall and lanky person with long arms