Yup, for years. I tend to go minimalist. MFJ QRP Cub on 20 meters, CW only. Now days there's probably an iPhone app for PSK if you are into that. I generally use 8 AA cells, a homebrew tiny CW paddle, and a 1/2 wave wire against a 1/4 wave counterpoise (sometimes the counterpoise isn't needed), tuned by a simple LC network that weighs under an ounce. Sometimes I bring a lightweight, tuned, dipole. The weight is the same, dipole vs. 1/2 wave wire/tuner.
What you want to do is more than I like to carry but I'd like to hear what you come up with. If you have an unlimited budget, Elecraft makes a dandy trail radio.
paul, texas KD5IVP