>I would like to hear what other PIClisters use to protect their designs.

If you really wanted to hide the design of the chip buy them as die and
package them with the pinout rotated compared to the standard chip. That way
at least it makes the pinout match less obvious, especially if adding extra
power and ground pins - someone mentioned a while back that die they bought
which had A/D converters had a separate pad for the A/D power which got
wired to the adjacent pin for digital power when the device was packaged.
Bringing these sort of pads out to separate pins will certainly be a first
line in helping fool reverse engineers until they decapsulate the item.

It may even be possible to get microchip to do this for you if buying a
million in one hit.

The other possibility would be to mount the die direct on the PCB under a
blob as has been mentioned in the decapsulating thread.

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