If you only have one outlet available this tiny AC power splitter comes in handy.
The device measures 55 x 37.3 x 12.5mm and provides 2 additional standard AC outlets by plugging in-between a power adapter and its cable.
Looks like the Moenegallet (strange name) is available in Japan.
Hong Kong based gadget shop Brando is offering the Moenegallet (made by Moons) for $16.00 internationally. The AC gadget has a maximum power usage of 400W.
See also the Powerstrip Liberator.
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