Mobile phone: is useful because you can phoned from everywhere that you need.
Remote control: is very useful for watches quicklyt he programming of every chanel.
Microwave oven: is useful when you don't want cook and you can heat some precooked foot up.
Memory card: is usefull to stored a lot of photos in a long travel abroad.
Digital camara: is useful becoause you see more clearly the shoot that you want