> Perhaps the reason that some have suggested the lights blink faster as the
> load gets higher is that the current range is 1s -> 2s -> 3s -> 4s and
> that people don't percieve phenomenon under 1Hz very well.  Perhaps a 
> suggestion would be to start the blink at a faster rate at load=0, like
> 10 blinks per second, and get slower as load goes up [...]

The original hack made to 386bsd (0.0), I remember well.

It was a change to the idle loop.  Basically, there was a static
counter in the idle loop, that was incremented each time the idle
loop was entered.  Every 4 or 8 (something that is easy to divide
via a shift :-) counts, the led output was shifted one position
in the direction it was going, or reversed in direction, and also
shifted a position.  (Otherwise, it would have an annoying "lag"
at the end bits in the LED display.)

(Of course, it was entirely machine dependent, and just smacked the
correct values into the latch on the parallel port.)

-Kurt