On the topic of traveling light, I have a guiding philosophy that helps quite a bit: Whenever possible, I charge my travel devices with USB.
In general, I charge things at night in my hotel room, so I turn on my laptop and charge devices off its USB ports. This approach comes in handy when traveling internationally, since I only need an international travel adapter for my laptop - not all the other devices.
On occasion, however, I need to charge one of my devices when it isn't convenient to boot up my laptop (after all, the laptop must be powered up to provide power to the USB ports). In those situations, I use a little travel charger, which I originally purchased for use with my iPod Nano.
This works for my Treo 650, my iPod, my camera, etc. and means I don't have to carry a bunch of different flavors of chargers.
I also carry a USB car charger in my suitcase, just in case (not in my laptop bag, since I don't use it as often). This can come in handy on road trips, long treks without my laptop, and also works in cars outside the US (in case I forget my adapter, or it's too bulky to carry along).