We used to tie a half dozen rubber bands together and then a half dozen more in to a ball at the end. With practice, and fully cocked with one arm streteched all the way back, the front of the band held firm between the thumb and the bend in the index finger, most of us could splat a fly from 10 feet, cielings too. Sometimes we'd miss, making it a sport of sorts.
When they mess with me where I sit, I sometimes note their flight path and they seem to repeat it more or less. When they on the airborn return, you can play batter-up using a good magazine and a good baseball-bat swing. The accompanying thawt is priceless. It usually doesn't kill the fly, it just knocks it senseless. Then you go stand over it, pronounce the sentence, and proceed with execution.
FYI: The best way to kill a fly with your hands is to clap your hands over them 1 inch above, 1 inch behind, with approach from the side. Since we are slower than they, they will be where your hands are about the time your hands clap duruing their escape. Gloat with each death, that you have outsmarted the fly, and used your brain to make up for your lack of speed.