The machine is not cheap — $1,400 for the unit which can produce up to eight gallons per day (it stores four gallons) and it uses about the same amount of energy as a small refrigerator — but according to the EcoloBlue website, excluding the cost of the device your water will cost about 20 cents per gallon.
And the water is very, very clean. The technology looks like it was designed by a descendent of Howard Hughes. There are 11 purification steps:
1. Electrostatic air filter (to take out all the dust and particulates in the air)
2. Condensing coils coated in food-grade plastic
3. Main carbon filter
4. UV treatment to kill bacteria
5. Sediment filter
6 & 7. Two-stage pre-carbon filter
8. Reverse osmosis
9. Tank UV filter
10. Dispenser UV filter
11. Final screen
There is also an optional process to introduce minerals back into the water, since reverse osmosis is known to produce "hungry" water that leaches minerals out of your body.
If you can swing the initial cost of the unit (and the yearly filter replacements) it is probably the cleanest water money can buy and more than cost-competitive with water delivery programs (usually $1+ per gallon).
But perhaps more interesting is its off-the-grid appeal. If you have solar panels, you could ensure a steady supply of water even if something goes wrong with the municipal water supply — handy for that earthquake or terrorist incident.
EcoloBlue is not for every household, but my guess is it will find a niche market.