>reset

If you have a spare IO pin connect it to the MCLR line. When you want to
reset set it to output and drive it low. The reset will tristate the pin
again. RA4 on PIC16F84 is excellent for this (and placed right too) ;-)

The watchdog method works better however (you should be using a watchdog
in your products imho).

I have a product that runs with WDT on but deliberately allows the
watchdog to trip only while running in the idle loop. This makes the
device entirely reset all the time every about 2 seconds. I use no
brownout and no regulator. Runs off batteries (3 x AAA) with no kind of
reset problems.

Peter