Computer, Phone, and other electronic gadgets need to be charged. I carry two packs: “mains power” and “in-plane power” plus a spare laptop battery.
My “model” is to go for USB (preferably micro-USB) power for all gadgets. A laptop computer – with enough USB ports – can therefore be the charging hub. Ideally the laptop has “USB bower when turned off” mode.
The Laptop itself needs power. I selected the smallest possible 100-240V AC to laptop (15v) power supply available (Its the standard Toshiba R600 unit which is quite tiny).
I then changed the mains cord from a long heavy one, with a UK plug, to a very short cord (from Japan) with a US/Japan 110V mains plug. This works in shaver sockets as well as in US and Japan, and is nice and small. I then carry the smallest US to UK adapter I can find, plus a US to 2 Pin european adaptor. This set up means I can travel almost anywhere in the world, including the UK, and get power to my laptop.
As a seasoned “roadwarrior”, I used to carry two bits of “chopstick”, a screwdriver and I used to just have “bare wires” for the power supply. If you had time, and took teh risk, this was quite flexible. If you were around in the 80’s you often had to use wire strippers and screwdriver to wire up your modem to a hotel phone outlet – so that way of working was standard! Nowadays, an extra 60g for teh adaptors is fine, plus you can’t carry a screwdriver through security any more.
For charging phone and bluetooth headset, all that is needed is a USB to micro-USB cable, and I carry at least one of those.
Finally, when travelling on a long plane flight, in-seat power is often available with a 15V em-power socket. I therefore carry the lightest adapter that can charge my laptop from in-seat power. This is the Kensington 120W DC to DC adapter. It has teh benefit of charging from a 12V DC car cigar lighter socket as well.
NOTE: I tried using various DC/AC to DC converters, like teh bigger Kensington 70W device. I found these heavier than the two small seperate items. Hopefully I will find something better during 2011.
I also carry a spare laptop battery. The Toshiba battery is very light – about 190g. This gives another 7hrs usage on my laptop – ideal for longer journeys without seat power, and it is vital if you need to charge your phone from your laptop and you don’t have mains or seat power available.