seeing that my parents are from [undefined country], i can tell you first hand that my guts are most certainly made of steel and that my extended family even have begun sprouting metallic appendages. go ahead, blame the water. but we all know its got something to do with cellphone use

It's not so much having "guts of steel" as it is being used to the local flora in the water. Though there are places where no one should be drinking the water without boiling first.

I can't imagine ever feeling confident that something so silly-looking would actually be effective at sterilizing water. But I bet you'd make lots of friends in the cantina while you were stirring your water with your little magic light stick. It should come with a sign that says "I'm rich and I think my health is more important than yours!"

I use an UV filter on my pond at home, its good at killing bacteria and cyanoalgae and thats it. Aside from that the water is still poisonous filled with chemicals that would rot your innards. If you need somthing like this you need a real filter too.

Didn't Steve-O from Jackass say that every country he goes to, the first thing he does is drink the native water and he's fine for the rest of the trip? There is something to be said about getting your body to adapt to different environments. Holy crap, did i just use Steve-O as an example of a smart thing to do?

I always wondered what they were using at the water treatment plant. Now we know.

Actually this is somewhat old technology. I recall SteriPen first making an appearance about a year ago. Plasmafire is dead on about how this UV tech is good in killing harmful bacteria, virii, etc. and useless to against chemicals and heavy metals. But it's fast. Sure you pay a premium for the speed but there's nothing else on the market that can kill of harmful bacteria, virii, etc. Pills take upto 4 hours, pumps are slow and muscle tiring (at least some of them are). Additionally, pumps usually don't remove smaller bacteria/viruses (unless the pump has an ionized filter). Whereas this niffty gadget does it very quickly. As for the taste, you can run the UVed water through a charcoal filter to remove the taste. Or some Kool-Aid. Oh Yeah!

A lot of people develop resistance to certain microbes etc. over time, or you just have some parasites in you that take care of it. Of course it is not "tasty" but humans have survived for aeons with those nasty things around you. Of course with most of us coming out of "antiseptic" environments (Antibacterial soap anyone?) environments are just going to succumb right away once the first bacteria entrs our system.

There is also the Aquastar Plus (http://uvaquastar.com/) which is cheaper, lighter, screws straight into a 32 oz Nalgene, and also comes with a LED bottle light (like the Firefly)...problem with UV is that it is not necessarily effective in dirty water as particles will block the light; so you will need to prefilter. I looked at these and ended up going with an MSR MIOX for backpacking (uses electricity + NaCL to generate Chlorine Dioxide & other Cl oxides), which is smaller and allows you to verify the treatment was successful (unlike UV)...downside is, you have to wait 30 minutes for 95% of Chryptosporidium, or 4 hours for 99.99% - how much of an issue that is, is debatable. Backpackinglight.com has some excellent discussions on this!

Does this also work on thai hookers?