I guess I just did, but not on purpose. I keep a couple of 'long term' experiments going in about 5 1/2 gal jugs. I call it my bug farm. Instead of air locks I just keep the caps on loosely. I noticed something crawling up the side of one of the jugs one day (see pic) and realized they were maggots. I guess that lid was a bit too loose and a gnat was able to crawl in. This was in a jug of wort with Goudenband dregs from 2007. So it was fairly acidic and alcoholic (at one time at least). I was surprised to find that those maggots could survive and thrive in that solution.