Finally, the beginnings of a correct approach to this question.

First, we can't really answer because we don't know specifically where you would be backpacking. The comments about line of sight are, of course, correct, but repeaters may indeed exist where cell sites do not. The American Radio Relay League (ARRL) publishes guides to repeaters and a Windows program (which I haven't recently tried under Wine) that can somewhat automate the process.

N4RKY

It is true that the Skype client works great with ALSA. At least on my laptops, however, pulseaudio removes the ability to configure audio devices within Skype. Skype's audio configuration allows you to configure distinct ring, audio, and microphone devices. I'll probably get flamed by pulseaudio advocates, but getting pulseaudio to configure any audio devices appears to me to be more in the realm of magic than actual function (which is why I now routinely uninstall pulseaudio).

I'll agree with the open software advocates on one point though: I'm basically looking to phase out Skype and use Twinkle more. As far as I've heard, Skype still hasn't made their code available even for a security audit and still hasn't satisfactorily answered questions about any possible back doors for three-letter government agencies.