Not a huge bargain but hey, anything FREE is good!
I came across this deal posted on Facebook and I called up the place to confirm because there is no coupon code needed. You pick which 1.25L drink you want once you go to pick up your food. I'm going to give this a go tonight.
Sorry, these guys are only in the northern Perth suburbs.
EDIT: just updated, minimum $10 spend.
$1.60 for a dim sim, ouch.