Right after reading Geoff's comments about the difficulties of photographing bottle flies, I sat down to dinner outside and was joined by a bunch of them. After we were done with dinner, I stopped shooing them away and let them eat our leftovers while I ran to get a camera and flash. Here are two shots of flies drinking from our salad bowl. I used a highly diffused flash held at the front of the lens (a stofen, extra diffusing plastic inside, and two layers of paper towel on the outside. Despite some dodging, you can clearly see the problematic reflections Geoff referred to. Still, they are photogenic critters.
C&C welcome, as always