As everyone knows, the Sydney airport is horrendous in terms of charging a "gate fee" for simply getting on the train at that station. Not being on the train there, getting on the train there. You could, in fact, go significantly farther than the airport and not pay with, say, a MyMulti; however, if you want to get off or on at the airport, you're more or less doomed. Until today!
This is a fantastic little tidbit if you've already got a MyMulti, are coming from the north and don't happen to be in a rush and figure an extra bus trip is worth the $12. Oh, drat, that was supposed to be the fine print. Nevermind. Here's what you do: get off the train at Mascot, then turn left and walk to the lights, cross the big road, walk a smidge more and wait for a 400 at the handy dandy little bus stop. Hop on and presto! In ten minutes or so you'll be at the domestic terminal!