Emergency International Plug to US Plug (Electrical Outlets)

I just got a Sony Ericsson P1i and I live in America so they gave me a plug converter (rounded international plug to standard US two prong plug)

and I went to NY for New Years Eve and I happened to leave the converter back in Philadelphia

so I was thinking how I could charge my phone

and my dad came up with an idea and here it is

Any standard US two prong plug that isnt being used
(Meaning not a device that turns on immediately or a transformer) ( I used a night light without a bulb)

The rounded plug which you need electricity for

A two or three prong outlet

Take the rounded plug and put the two prongs of the US plug imbetween it and then plug it in carefully and squeezing the rounded plug near the outlet so it stays without you holding on to it

Or....

Plug in the outlet but not all the way so you leave a little space
then while holding the US plug squeeze in the rounded plug

Look at the pics you'll know what I mean

Here is a video of how to do it

Yes Yes I know there is no sound didn't feel like talking

And the vid is really bad quality but you get the jist of it at the end

http://www.metacafe.com/watch/1013639/emergency_international_plug_to_us_plug_electrical_outlet_convert/