I recently came across a list of "killer gadgets" that you should have when you hit the road. It was a bit too flashy to be practical, though, and missed the necessities. But it did lead me to think of the dozen things that I carry in my "Widget wallet": most are small, universal, and USB-based so that I don't need to carry more plugs or cables than necessary.
Point and shoot with image stabilization, it takes sharp pictures. Zeiss optics and a bright screen on the reverse side: the low-light pictures have been very good, and the pocket size is great.
I carry a UK card, a Dutch card, and a US card in my wallet. I unlocked the phone for 10 gbp down at the market in Cambridge.
Stylish and light, good sound quality, and simple and reliable pairing.
It works for US, UK, and European plugs, and for small loads such as camera chargers and laptop computers. A small power inverter with universal plugs for the cigarette lighter in a vehicle is almost as good.
Great for heating water, soup, coffee, or nighttime cold medicine.
Pricy but indispensible in Europe. You simply can't translate street signs, read a map, shift, and watch traffic, all at the same time on winding city streets. The "Map Lady" seldom fails to point out the route, estimate times, find gasoline and restaurants, and warn of speed traps.
Holds hours of music or podcasts, doubles as a memory stick, charges and transfers through the USB connection, accepts any earbuds or headset. Includes an FM radio and voice recorder.
The combination unit is nice, although I'd prefer a green pointer to a red one.
Good for transferring photos out of the camera or exchanging them with others. It also handles SIM cards.
About as big as your hand but holds an amazing amount of data. I use it for caching pictures and archived files, as well as DVD movies that I've ripped to it for viewing in hotels on rainy night.
A sniffer that tells you when you are in range of a WiFi hotspot: I've used it to find sweet spots in hotels, and open ports along residential streets late at night when I have to have a connection in an unfamiliar town.