Painting Behind a Light Fixture
I needed to paint behind the globes on the light fixture above the bathroom mirror, and I couldn't make room to get my standard 2-1/2" paint brush to work. The nuts holding the globes on were too tight, and the light fixture was too difficult to remove. I couldn't maneuver the brush to twist and turn it to cover the wall (and not the mirror and light).
I sawed the handle off an old paint brush as close to the ferrule as possible, and trimmed off a quarter of the bristles with kitchen shears. The brush was worn to practically dust broom status, and so I also thinned it down a bit so there weren't any rouge hairs stocking out.
The thinner brush (barley) allowed me to cut-in the gap without getting paint everywhere, and the shorter handle let me twist the brush behind the globes.