I once participated in a (different) forum, that had people adding MSG to their microbrews, in the hope that the yeast would then convert some of the added MSG into GHB along-side the alcohol. This wasn't as wrong-headed as it sounds, since trace amounts of GHB is sometimes found in wines.
Anyway, I don't remember anyone being able to show that this works; but this thread reminded me a bit of that other thread.
Happy brewing everyone!