When a character does something particulary in character give him a reward point.
When he does something out of character or bad, such as tell the other players
information his character didn't know, take away a god point.
Keep these secret if you really want to psych-out the players. They will get
freaked out when they see you writing down something after everything they say!
The players can then call upon their gods for help when they need it, if they
ask for small favour that will cost them a small amount of god points, a large
favour will naturally cost more. If they have zero, or negative god points,
or if the favour would bring them below 0 god points something bad will happen
instead! They player could get struck by lightning etc etc.