catatonic
adj. Describes a condition of suspended animation in
which something is so wedged or hung that it makes no
response. If you are typing on a terminal and suddenly the
computer doesn't even echo the letters back to the screen as you
type, let alone do what you're asking it to do, then the computer
is suffering from catatonia (possibly because it has crashed).
"There I was in the middle of a winning game of nethack and it
went catatonic on me! Aaargh!" Compare buzz.