Hi hippiechix,
I agree with some of what my co-posters wrote but still would like to add my two cents:
1. First of all: yes, by all means do get a cell phone for your trip!
More than just beeing a covenience it, it might save your behind in one situation or another.
I´m so glad that the times are long gone when 2 travellers had to meet "two moons from now by the water fall at dusk". Forget that and top it off by taking TWO mobiles along, so that you girls might opt for splitting up instead on depending on that "radio girl"
2. Yes, forget mp3 and that camera function since it sucks waaaay too much nergy from your battery, plus the camera is crappy. Go for separate items and you´ll benefit from it. Since battery life is definetly an issue, get a second battery and/or a solar battery charger.
Also do check the frequency used in that foreign country. If it is the same as in the US (as it is the case with Bolivia) there will be no need for a new tri-band mobile and you´ll be able to keep your phone.
3. You wanna go cheap?
Then get a local prepaid phone card (SIM). Using that will result cheaper that using your American SIM card.
The down side should you be travelling through several countries is: you never can be sure where to get that next prepaid card and if you´ll be able to use it instantly.
And depending on where you´re hiking: you can´t be sure to have network coverage.
4. You wanna go safe?
Check
www.thuraya.com . They offer that jungle coverage and the matching mobiles that work in most places. And you call use your old SIM card in those phones too. Their downside is clearly their price point.
But no matter what you decide - DO take a mobile with you!
Take care!
moogley