Boiling is a great solution when you have everything that is needed and boiling is truly the best way to eliminate the contamination present. For example, you must have a consistent source of fuel. This is something that is in short supply for many poor people. For researchers, this is a matter of collecting, buying or bringing it with you. As far as contamination, boiling is great for killing bacteria, parasites and most viruses but it will not kill something like a prion. Boiling is also a terrible idea if your water is full of nitrates since it will actually concentrate them and make the water more toxic. Indeed, if toxicity is a concern (for example in rivers where gold mining is happening with heavy metals) then you have to filter. Finally, boiling takes a huge amount of time and results in water that is flat and, especially if done on a camp fire, frequently full of ash/particulates (again, no filtering). No one, not even poor folk or researchers, want heavily turbid water as a refreshing drink.

Brigadeiro! Wow. I haven't done lasagna yet but I think that needs to happen soon...

Melanie, I'm glad you like the site. Apologies for the delayed response, I've been way up river for a couple of months. Overstaying the visa is generally a bad option due to fines being levied when you try to leave the country (though if you're only a few days over this isn't a big deal). The one-year visa isn't so bad if you get help from someone who has gone through the process where you plan to do it yourself (i.e. don't get advice from someone living in La Paz if you plan to get your visa at Migracion in Trinidad, Beni. The requirements, waiting periods, costs, etc. will vary dramatically). But you need help from Bolivian nationals, a place of residence with utility bills, med exams, blood work, etc. Let me know if I can help further.

Hey Andrew! I'm glad you found it helpful. Drop me a line or leave a note here if/when you need any further help—there's plenty I left out for the sake of brevity and clarity.

Thanks for the comment Rachel! I'm glad you like the site and I hope you'll keep us in mind as you get closer to going to the field (and maybe write a post or two!). Until then, your suggestions sound great and we'll add them to the growing list. I especially like the idea of having a regular question and response. More soon...

Thanks for the help dhlizard! Now I can relax and just keep an eye out for a new version of Redsn0w.

I'm using RedSn0w to attempt an iOS upgrade from 4.3.3 to 5.0 on a GSM iPhone 4 firmware 04.10.01. After creating a custom IPSW, going into pwnd DFU mode and almost finishing the restore process in iTunes I get a 'this phone isn't eligible' error. I've checked my hosts file in OS 10.7 for gs.apple.com entries and there are none to be erased, just localhost and broadcast host. I am able to get out of DFU with recovery but am left with no upgrade. Since editing my hosts file doesn't seem to be an option, are there any other solutions?

Much obliged and keep up the good work!