Basically you have to fling it upwards fast enough before gravity has a chance to act upon it.
I have the 11" MBA and with the Speck clear plastic shell it has extended bumpers on the rear two feet of the laptop. This allows it to be opened with one hand and not tilt at any point. I like the Speck hard shell case b/c it's super low profile, protects against scratches for increased resale value and it makes the lid a pleasure to open compared to it's normal naked self.