ORing conditions

Hello,

I'd like to combine rules with OR. I can use

:0
* rule1
{
  ...
}

:0
* rule2
{
  ...
}

and so on, but this is cluttering the rc-file.
Another thought is defining a variable instead of performing some
(complicated) actions in the {...} and later ask for the variable to perform
the action.
Finaly I though of inverting the conditions, e.g.
:0
* ! rule1
* ! rule2
{ } # empty action
:0 E
{
  ...
}
Does this work (any possible pitfalls)? What is the preferred method?

Thanks,
        Axel Thimm.
-- 
Axel Thimm   thimm(_at_)physik(_dot_)fu-berlin(_dot_)de thimm(_at_)ifh(_dot_)de