My first thought as well.

Wikipedia's first hit:

"Extraction of a liter of xenon from the atmosphere requires 220 watt-hours of energy.[52] Worldwide production of xenon in 1998 was estimated at 5,000–7,000 m3"

Sounds like we have some scaling issues before this engine puts us on mars on a regular basis.

Supposing this is true, it took this long because everybody thought that dental X-ray was harmless.
(tumor growth in less than 1:4.000.000 images, regardless of the type of tumor.)

Dental X-ray uses less than 0.01 mSv per image.

You absorb 200 times this amount every year, year in, year out. all your life. And if you live in a place with higher background radiation, this number goes up quickly.

So it is hard to prove these tumours are caused by the exams.
Lets wait and see what comes out of this.

Usually these kind of studies have some form of bias thats not adequately corrected for.

http://imgs.xkcd.com/comics/security.png

Surprised to see noone has opted the easiest solution yet!

Make some random calls to people in Saudi Arabia, Soedan, Ethiopia, etc.
Make sure to mention words like bomb, white house, infidel, plane etc etc.

If some one steals your bike, just call the FBI and ask them where it is.

Sort of the same for me.

For me the route was also windows -> linux -> OSX.

However, during my linux period i grew accustomed to finding great software doing almost everything i could wish for within a few clicks/google searches.

For OSX its the opposite. For every small task that i want to accomplish, i seem to need to pony up. Every small time programmer tries to make a buck with his little program. Nothing wrong with that, but where are the Free/Libre alternatives?

For now, after long searches i end up installing untrustworthy programs, because i'm used to get it all for "free" (he, i am Dutch). My problem, sure. But a lot of people like me would fall into these kind of traps.

I know the plans to put one of these into service are almost finalized in The Netherlands, spanning the "afsluitdijk"
http://wikimobi.nl/wiki/index.php?title=Zoet/zout_watergrens

But i think the Norwegians beat us all to it:

http://www.statkraft.com/energy-sources/osmotic-power/

Believe me,

I do not want you to see my "adult projects"

thats something for the privacy of the home, you pervert.

seriously,

what i meant to imply (and you obviously failed to grasp); Slashdot needs to filter away stuff that is far from impressive. If his mirror had had a diameter of 10m, than that would have been newsworthy for a 19-year old. I'm sure younger kids have achieved more impressive results than sticking some glass chips on a 1m metal plate.

also, is 19-years not being an adolescent?

5800 mirrors, the size of fingernails. Glued on an already parabolic disc.

Couldn't he just have spray canned it with some reflective paint??

I imagined at least 10x10cm mirrors. Now that would have been "solar power".

wake me up when he heating his house with this. This little satellite disc is kids stuff.

Wasn't another good reason to use salt, that molten salt has excellent thermal conduction properties??

As, you barely have to pump it around, for the heat to reach the reservoir.