The name 'PinStack' defines the nature of our community:
PIN [. pin] noun - Each BlackBerry device has a unique PIN (Personal identification number), like every phone line has a unique phone number. PINs are up to 8 characters long e.g. 20202020. Users can send messages directly PIN-to-PIN and thus they gather at PinStack to find other BlackBerry users in their area.
Stack [. stack] verb - A pile of things in large number more or less neatly arranged one on top of another. In this case stacks of BlackBerry (PIN) users.