We have added the following home brew rule to our Pathfinder game:
Clerics can forget a prepared spell of equal or greater level (not domain) and use Consecrate or Desecrate (per alignment) in its place.
We came up with this rule, because what is a Cleric to do if he/she runs across a shrine/altar/etc. of a god of an opposed alignment? Obviously, he/she would want to break the bond. It's unlikely that many characters load consecrate/desecrate all of the time. So, to promote role-playing of Clerics, we added this home brew rule.
Thoughts? Could you see using this in your game? Positives / negatives?
