[anigbrowl]

I made a lot of DK jokes after the Segway came out - I thought it was a solution in search of a problem, and its high price made it an expensive toy more than anything else. But I was impressed with his water purification machine last year, and I share his frustration* with much of our technological effort and spend going towards frivolous things.

* while recognizing that some of this stems from not being able to make even more money :)

Article ended just when it was starting to get interesting though.

[bcl]

His water purification system is really amazing. You would think that all of the 'help save the worlds poor' non-profits would be jumping all over it. Here's the Wired article from last year on it - http://www.wired.com/wiredscience/2008/03/colbert-and-kam/

[ars]

Here's why: http://www.appropedia.org/Slingshot_water_purifier

It costs WAY WAY too much. He "hopes" to get it below $2000, which means right now it's more than that. And after you read the $/L estimate, add in the cost of fuel and you'll see the device is not cost effective (when compared to other devices that do the same thing).

According to here: http://www.ecofriend.org/entry/powered-by-cow-dung-slingshot... the system cost is $5200.

[10ren]

It would come down in cost with economies of scale, and improved production techniques, and... in 20 years, it would be out of patent.

I think there is a moral dilemma when someone creates something immensely valuable, but wants to be paid for it. But... wouldn't a world in which people didn't get paid quickly become rotten? And is it any different from people needing money for life-saving surgery (because the surgeons, hospitals and suppliers all want to be paid). See also the pied piper.

Factual content: there's a camping device for purifying water with ultraviolet light http://www.steripen.com/ but it just kills things, and won't remove salt or arsenic.

[nazgulnarsil]

how is it superior to simple bleach based purification? http://www.survivaltopics.com/survival/better-than-bleach-us...

[anigbrowl]

See, that looks cheap to me. DK claims 1000 liters/day for a cost of 0.2 cents/liter; let's be pessimistic and assume 500. (Maintenance would be my biggest worry, but let's keep it simple.)

Now if we take grinding poverty as a per capita income of $1/day and consider a village of 100 people, that means everyone in the village could have 5 liters of pure water a day at a cost of 1 day per week - a 14% 'tax' for 1 year.

That's a big economic hit for a very poor village, but it would not surprise me to find that such a village might lose more than 14% of its productivity to a combination of acquiring cleanish water and lost productivity due to water-borne diseases.

$5200 is not big bucks to us in the developed world. Surely it would not cost too much to buy 5 of them and do a year long comparison of 10 villages where half of them have the system and the other half serve as a control. Even if you add in setup costs the total bill for such an experiment would only be $75k.

[clistctrl]

To be fair, the segway wasn't the initial problem they were trying to solve. It was a byproduct of something larger. His team was working on a wheel chair called the iBot (http://en.wikipedia.org/wiki/IBOT) while making the wheel base they realized it was fun on its own and expanded that idea to the segway. The iBot is actually trying to solve a real problem.