I'm always interested in seeing alternative and obsolete systems, as they can show the historical development quite well. They sometimes explain why things are still done a certain way today.
There used to be some overhead distribution systems which looked like 5-wire in some districts here. They were actually just a standard 4-wire Wye with the fifth wire used to switch pole-mounted contactors for street lights. On some old poles it's still possible to see the fifth insulator bracket in place, although the cable and insulators themselves have been removed. I haven't seen one of these systems since the 1980s, and they were rare by then, but there might still be one or two in use somewhere.
If you look at old photos of many British towns, the "town centre" area (downtown) was often festooned with cables.
Apart from domestic/commercial power and telephone, many were for the trams (what you would call a street car or trolley) or their successor, the trolley-bus. The latter were electrically powered buses running on normal tires for greater maneuverability, and thus needed two pick-up arms and twin overhead lines.
All of that is gone, and over the years there has been a gradual move toward underground power & phone lines, much to the pleasure of many who obviously don't share our enthusiasm for looking at electrical systems. (Strange people! [Linked Image])
Drive through a typical British town today, and you'll certainly see less overhead linework than in the average U.S. town.
*

P.S. The double-ring is certainly distinctive, although when simulated in movies or on TV the timing isn't always accurate.


[This message has been edited by pauluk (edited 11-25-2001).]