When you reach the room with the Supercomputer, immediately hold down and right (or down and left) as soon as you enter the room. If you did it right, you'll end up in the room with the final boss and skip the part with the Supercomputer altogether! This makes beating the game easier because the timer that's normally activated after destroying the Supercomputer isn't there. So, in effect, you have unlimited time to beat the final boss and escape.
Taken with permission from Flying Omelette.