I heard that some parts of Scandinavia used a 220V system operating from a xfmr which was center-tapped to ground so that each leg was only 110V to earth (i.e. similar to the American 120/240V 3-wire system but without the neutral extended to the house).
In the 1950's there were three systems in use: 110V, 127V and 220V. (DC was also used in some places.) I'm too young to know when these were converted to 220V only.
The system you describe is rather uncommon these days, but I worked in an office a few years ago where every room had a blue CEE 17-socket with this system. The rooms had been used as labs (or something similar) previously, so I suppose it was a safety feature. (The wiring was rather new, with a consumer unit with RCD:s and MCB:s in every room)
Also, a small number (perhaps single digit) of buildings with their own transformer still use this system for general purpose sockets. In some cases a 127/220V system (3-phase) is used for safety reasons. (I've seen it in labs with their own transformer.)
However, I would guess that 99.9% of the houses are supplied with the standard 230/400V.