There are a few things I'd take issue with in this post. I'm currently 5 months in to a South American trip, and developing along the way (frontend dev).
Firstly, a 90L is absurd and far, far too large. My girlfriend and I carry 38L Deuter packs that do the job perfectly, without breaking our backs.
If you're American, travel in South America can be difficult as visa's are required for almost every country. USA, Canada and Australia are forced to be between $80 and $150 when arriving by air in to Buenos Aires or Santiago. Australians also need a proper Brazilian visa to enter the country, and a flight out of Brazil.
It is definitely possible to work while you travel, but the added stress of having expensive pieces of hardware (MBP, iPad etc) with you while you're in these places can sometimes not be worth it.
I would highly recommend working your butt off and saving minimum $10k, potentially $15 / $20k and then leaving your tools at home and getting out there with the least amount of tech as you can manage. Still jump online, network, Twitter, meet folk along the way but focus on what's important; travel.
Brazil requires Americans to have a visa but it's the only country in South America to do so. Others charge a reciprocity fee - Argentina, Chile, Bolivia, and possibly others. But you can pay it when you land and they don't always charge it depending on whether you enter in a big city or a small border town.
Regarding your issues, I have issues (well, issue): Travel in South America does not require visas for an American. It is very easy to travel here, we've had no problem for the last 6 months.
Bolivia charges a reciprocity fee upon entry for all Americans. Other than that we haven't paid anywhere else. That said, we've done land border crossings since Colombia. Brazil, Argentina, and Chile WILL charge a fee when you fly into them internationally.
We've also travelled for 5 months through the poorest countries of South American with an iPad, MBA, 2 iPhones, 2 Kindles, and $2,000 in camera gear. This doesn't cause stress, you just don't flaunt these things openly in public.
I however agree with the sentiment of not working while travelling.
That's great to hear about traveling here as an American. I was only going off what other Americans had told us, they had said it was harder than it needed to be. We have just about the same gear you're traveling with, and I totally agree; just don't flaunt it around in public and you're fine. We haven't had any problems at all (so far!) with that.
As a matter of interest, which hardware (specifically laptop) did you take along? I'm about to do a trip and am unsure whether to take a MBA on the road with me.
I've got a 13" 2009 MBP w/ 2x internal hard drives. Also have a 3rd gen iPad. We sync everything to DropBox, but had major problems getting our SLR shots and my work synced while we were in Bolivia, the internet there was terrible. Argentina, Chile and Brazil have damn good internet.
Firstly, a 90L is absurd and far, far too large. My girlfriend and I carry 38L Deuter packs that do the job perfectly, without breaking our backs.
If you're American, travel in South America can be difficult as visa's are required for almost every country. USA, Canada and Australia are forced to be between $80 and $150 when arriving by air in to Buenos Aires or Santiago. Australians also need a proper Brazilian visa to enter the country, and a flight out of Brazil.
It is definitely possible to work while you travel, but the added stress of having expensive pieces of hardware (MBP, iPad etc) with you while you're in these places can sometimes not be worth it.
I would highly recommend working your butt off and saving minimum $10k, potentially $15 / $20k and then leaving your tools at home and getting out there with the least amount of tech as you can manage. Still jump online, network, Twitter, meet folk along the way but focus on what's important; travel.