From playing B Nomic, I've seen one potentially useful idea: transactions. I'm not sure if everyone wants them, but let's see:
Proto: Transactions (power=3?) Create a rule titled "Transactions" with the following text: A transaction is a method of announcing actions, contained entirely within "BEGIN TRANSACTION" and "END TRANSACTION". A transaction may have a list of assertions and may have a list of actions. If any assertion made within the transaction is not true at the time of the transaction or, alternatively, the time specified within the assertion, then none of the actions in the transaction take effect. If any action made within the transaction fails, then none of the actions in the transaction take effect.
