If you enable the watchdog timer, you have to issue CLRWDT commands to stop
the chip from resetting.  So you might wnt to disable it UNLESS you want to
use the SLEEP instruction to save power: have the chip wake up on a regular
time basis to do a job.  In this case, enable it, otherwise SLEEP puts you
to sleep until a power reset.  We use SLEEP in radio applications to sniff
for radio traffic once a second.  Of course, if you are using mains power,
you can replace SLEEP with a loop.  That's my main use of the watchdog.
  <edtodd@sni.net>    Ed Todd