I saw this on their front page.
look pretty simple, order your Fast favourite or Most Recent Order using sms (Domino's Account with registered mobile number required) and get 30% off.
1 Sign up for a Domino's account and add your mobile number
2 Place an order online and save your preferred payment method
3 Next time you're hungry SMS 'Pizza' to 0448 366 466 to place your order
I'll be trying this on Tuesday to see if you can actually get the Tuesday special even cheaper !!
I can not find the rules and small prints for this …