I also have a bunch of these things in my collection - more as a curiosity than anything else, since I never use them. I did, however, see a house one time (while on an EMS call) where THREE of these things were screwed into one of those porcelain keyless lampholders in the middle of the living room ceiling. Extension cords were plugged into this outfit and "radiated" out to every corner of the room, and then some. I was too horrified to look much further to see what was plugged into this mess. And surprisingly enough, we have not yet had a fire call at this residence...but I can smell it coming.
Mike (mamills)
At the risk of being lynched, I do have one of these in use in the closet socket (I never use a light in there anyways, so there's no bulb in it). It's used to connect two small strings of christmas lights which line my doorways (so I can just flip em on/off by the wall switch). Although I should just use a Y adaptor and two of those screw shell adaptors. There's nothing more than those two strings of mini-lights plugged into it.