From my experience in the Philipines 81-83, Visiyan Islands, lighting was the only thing I remember being served with electricity and in some areas as often as 2 hours a week (other places almost 100 percent of the time). I can not recall any receptacles though I know of homes which had TV's so they had to exist. If they had been horizontal it likely would have stuck with me as beeing odd. The light switches were all vertical (even the pull chains were vertical still rather than hanging horizontally as one would expect being that close to the equator and about to fall off the face of the earth).

Shane