Not sure if anyone will be interested but I want to go so thought I would suggest it :p
The Luna Cinema are having an outdoor screening of Labyrinth on a Friday evening, it would be a nice relaxed way to take advantage of the good weather.
There will be food and drink on site and it's advised to bring a blanket/chair to sit on although there will be some for sale on site. Doors open at 7:45pm but film will not start until 9pm.
Tickets are £12.50 on the website: http://thelunacinema.seetickets.com/venue/dulwich-park-london-se21/1221/default/1/200