Small Lightweight Travel Trailers What Is The Best Cheap & Small Electronic Device For Text Entry, With A Close-to-normal-sized Keyboard?

What is the best cheap & small electronic device for text entry, with a close-to-normal-sized keyboard? - small lightweight travel trailers

I want a cheap electronic device, small and light enough for entering text and basic editing functions can be used. You must have a keyboard that can be used to write in more detail (eg size keys).

You should also (of course) have a kind of easy connection to computer, the correct files / disable the device.

A laptop is too much. Even a PDA is too large (but folding keyboards).

The main objective would be to write, while driving in airports, etc.

Suggestions?