When Wikus is using the alien walker robot, he is seen picking up a pig carcass and launch it with something resembling an anti-gravity gun, a weapon type made widely known through the computer game
Half-Life 2 (2004) (VG). In
Alive in Joburg (2005), Blomkamp's short film of which this is based, the aliens appeared to have a very similar type of Anti-gravity Gun (though of much more power - they were able to lift vehicles and launch them a considerable distance).
more