Quote Originally Posted by Adzeh
It comes from lack of blood supply, usually in small areas like toes/fingers/hands. When you lean on a particular part of the body you restrict blood flow to that area and so muscles begin to contract and concerve oxygen.

When you begin to stretch the affected area you find a tingly sensation which is really the blood returning to the area and restarting the muslces.

The reason why you do not get pins and needles in larger areas like legs or arms veryoften is because arteries are larger and the blood is at higher pressure than in the fingers and so will get it's way through, despite the fact that you may be lying on them.
Yeh, I heard you get pins and needles because of restricted blood supply...