One of them was the open air cinema at Curtin House and it was so lovely that I thought it was worth mentioning here.
The rooftop bar shows movies every night except Friday during the summer. For $20 you get a stripy deckchair, a movie and an unparalleled view of the city. (I especially liked the shadows the skyscrapers cast against the projection screen.) The programme is eclectic, so there's bound to be at least one movie you want to see.
Drinks are available from the bar and there's also a burger and fries stall. Order at the counter and they'll deliver your food to your seat when it's ready.
A perfect night out.