The DeathStation 9000 (often abbreviated ds9k) is a hypothetical computer architecture often used as part of a discussion about the portability of computer code. It is imagined to be as obstructive and unhelpful as possible, whilst still conforming to any relevant standards, deliberately acting unexpectedly whenever possible.
With many C compilers, the statement i = i++; where i is an integer variable, will either increment i or leave i with the same value when run (the behavior is undefined). On a ds9k, it is possible (even probable) that executing that statement will cause demons to fly out of the user's nose.