I just got this tip from Nicola Kamper, who is currently cruising the Bahamas:
I learned something new last night. We had a potluck, and the flies came in droves to the food table. Someone recommended Tabasco, so I got my bottle, we swirled some onto a plate, set it on the table, and the flies disappeared!
I haven’t had the chance to try this — no flies where I’ve been, thankfully. I’d love to hear from anyone else who tries it: does it work for you or not?