sondod:
I gotta ask though, where did you 'learn' these
methods?
Seat of my pants... I was once doing sound design for a film, comedy, and they needed ambience for a laboratory scene (scene included bubbling flasks of chemicals, tesla coil-like electrical arcing). The bubbling in the flasks was done with dry ice in water, so there was no real sound to it, and it wasn't picked up on location anyway. So...
Large beer glass (pub style, pint), straw, mic, laughter, more laughter, "this is taking way too long", "sorry, but I can't stop laughing", and finally, a track!
Oh, and the electrical arcing was me recording the sound of an oil burner coil which I turned into a Jacob's Ladder using some coat-hangar wire. (I just happened to have an old oil burner coil lying around).