Here's what happens when Qantas QF631 (16:50 Bris-Melb) is running late, and Virgin DJ332 (17:10 Bris-Melb) is on time.
I saw these two coming up from the horizon almost next to each other, very close. As they got over our place I thought it might make a good photo, so dashed inside and grabbed the little Sony. Imagine my suprise when the Virgin aircraft turned across the QF flight! After another two miles, the Qantas plane turned on to a parallel path to the Virgin one.
They probably had 500 feet of vertical separation, but it was quite a thing to see.
Cheers,
Jason.