Anyone have any idea why the thermometer display in the overhead console
would suddenly start reading 0 degrees, occaisionally dropping to low,
low negatives (-75 was observed once!)? The rest of the display
(compass, Odometer, DTE, etc.) all works fine, so I suspect a problem
with the sensor itself... anyone have an idea where the sensor for this
thing is located and if there's any simple test procedure for it
(resistance measurement or something)?

There've been a couple other strange electrical problems as well: for
the longest time, the left-turn signal would stick on, sometimes
immediately on activation, sometimes after a couple blinks, and would
even stay on with the key turned off. All bulbs, fuses and relays
checked fine and it was only on left-turn that it happened. This
particular issue went away a couple months ago all by itself, after
being an annoyance for several months previously, and hasn't returned since.

Another more current oddity is that sometimes the wipers will go on
steady "low" when set to any intermittant setting, and when this
happens, turning them off causes them to stop instantly where they are.
This happens only very intermittantly and disappears as quickly as it
appears.