What are people drinking in this weather? I'm finding I'm drinking more than usual but I don't want to consume more calories than I have to!
Try the 'diet' / 'light' drinks like Cola Zero or Pepsi Max. They have no calories at all.
Water would be my advise. Not only does it fill you up, but it's necessary for your body to function properly.
I would stay away from carbonated diet drinks - they're a cocktail of chemicals.