Steve on Broadway notes that if you've bought Ticketbastard tickets for shows being cancelled through the strike, the full price of your ticket is going to be refunded, minus the $3.10 per-ticket processing fee and any delivery fees. Of course, Telecharge won't be pulling this crap. SOB suggests:

If you've purchased tickets through Ticketmaster, do what I have done in the past when a show has been cancelled -- call and politely demand all fees back. If you are told they cannot, politely ask to speak with a supervisor. Please note that it's important not to lose your temper!
If they refuse, contact your credit card company and set up a dispute with them. There is absolutely no reason why Ticketmaster should withhold any fees when you, as the audience member are not at fault.

Remember, the stagehands are not the enemy. And the producers are not the enemy. THE REAL ENEMY IS TICKETMASTER.

Strike against Ticketmaster. Now that's something producers and stagehands alike can come together on!