On second thought, an electrician probably knows where to get them himself.
[This message has been edited by rpxlpx (edited June 13, 2002).]
Indeed, I suspect that even most hotels cannot even use them due to the risk that someone will inadvertantly plug an 110v appliance into them when the outlet (or a plug in the outlet) is switched to 220 volts. (The plugs do have different shapes to prevent it from happening, but it is still possible). I have only seen the multi-voltage outlets in Europe where the voltage gets steeped down for American appliances or (in Britain) for shavers (many electric shavers in Britain run on 110v due to the customary proximity to water, so they have U.S.-style plug outlets near the bathroom mirror). It would be more dangerous to have multi-voltage outlets in a country like ours where the voltage could be stepped up accidentally.
If you still really, really want one because you frequently have foreign visitors, you would best look for hotel suppliers in a foreign country such as Great Britain (or wherever your frequent foreign visitors come from). If so, you would also need to specially wire those outlets all the way from the breaker to the outlet. It is not just a matter of hooking them up to the existing wiring. It is a big deal, not just a easy and nifty alternative.
[This message has been edited by Lawrence (edited June 17, 2002).]