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About a year ago I was looking for something similar to the Radio Shack Armitron I had as a kid. I ended up getting an OWI robotic arm for my kids, which is pretty cheap at $35 on Amazon, also has a USB control board for an extra $15 or so. You assemble it yourself, but it's fairly easy as plastic models go, even relative to Legos, and the build quality is pretty high for the price.

There's even code. to get the USB control stuff working under *nix . I had to make a few minor tweaks to get it to compile on my Linux box, and it's a bit basic, but it worked! Would be fairly trivial to build a web interface to it along with a webcam. The only downside is that it still draws power from D-cells, but that's easy enough to live with.

http://www.radiationnetwork.com/ (scroll down for details on Geiger counter model numbers)

You ought to participate here
http://enenews.com/
(wtf seems down at the moment??)

I used a CDV-700
(with the DU sample on the side)
http://www.civildefensemuseum.com/cdmuseum2/radkits/cdv700.html
Then I soldered together one of these.
Dollar Store Digital Geiger Counter Hack
http://www.pskl.us/wp/?p=289
Then pick a spot and do 10 minute tests.

The drawback is I wasn't measuring the "floor" before 3.11 so I have no low floor to compare against, but the best I can tell it's trending down currently, and if anything I am building my own floor.

I now have been measuring the floor long enough that I can tell which way the overall situation is trending. I started in the 850's June and it's currently down in the 550's October, we most assuredly got dusted by something.

Things I learned from all this?

I will never be able to detect hot particles with this equipment.

Stay away from the RAIN, as it brings the shit down out of the sky onto the ground, just like a water truck keeps a dusty road muddy and dust free.

If you have a whole house air filter which was installed before 3-11 I highly suggest you change it, when I tested mine it was literally a hot object, and let me just say that was an eye opener.

There's also some software that you could use if you can't find the dollar store pedometer parts. also, most pedometer's are similar so if you know electronics, it's a simple matter to modify from pedometer to pedometer.

There are a few others out there now helping people with analog meters.
http://www.imagesco.com/geiger/geiger-counter-accessories.html
http://www.instructables.com/id/Ustream-your-Geiger-Counter/step2/Free-Counter-Software/

Some other CDV-700 mods
http://home.comcast.net/~prutchi/index_files/cdv700pro.htm

Free Counter / Scaler Software
David Honigâ(TM)s free âoeCDV Counterâ program
http://www.anythingradioactive.com/CDVCounter/help.html (wtf 404 for the software, no problem use the guide there and download from our ham radio friends who wisely have us covered. http://www.qsl.net/k/k0ff/CDVCOUNTERZIP/CDVcounter-zip/

There are some charging money for counting software, I don't know about these, they look legit, I guess it comes down to your own abilities and what you want.
http://www.geigercounters.com/Software.htm
http://www.blackcatsystems.com/GM/page3.html

Opinion: If I lived in Japan, I would have sold everything and done anything to leave months ago.

Hopefully someone will mod this up so you (and others) don't miss the information.

Surpsingly complicated, couldn't find any simple practical answers. Sorry. I did find some nifty pictures though.

How about HTSC ring for enery storage?
http://www.imagesco.com/articles/superconductors/superconductor-energy-storage-ring.html
Years ago there was some interest in small strong fly wheels for energy storage.

Now the cool thing, of course, would be to use the iPod as the audio portion of a Geiger counter—maybe write a meter-face and radiation level recording app for it. It turns out that modern Geiger counter circuits are readily available as finished devices, in kit form, or even as a do-it-yourself project. (The suggested schematic is a bit retro: with a more modern boost converter you could conceivably get it even smaller and simpler.) I don't have the time right now, but someone should give this a go and let us /.ers know how it went.

Or rig toy motors (the kind that generate electricity when you turn the shaft, such as this) to your doors so that each time you open or close a door, you generate enough electricity to run a VCR clock for a few minutes.

doubt the existence of a superconducting loop (at least using materials discovered so far) that can run for years "without decreasing"

The resistence of a superconductor is zero. That is the definition of a superconductor. You can go do the experiment yourself if you like. Order yourself a superconducting ring, stick it in a glass of liquid nitrogen, and measure the current with a compass.

The current will take about a millenium to decay to half its original value, but that's due to magnetic fields, not electrical resistence.

Now, there are a number of technologies that you could potentially use to do this, from the mundane pumped hydropower, through a whole variety of steadily more exotic technologies like flow batteries, fuel cells, and superconducting current rings, but until they get cheap you can only use intermittent energy sources as a small fraction of your grid.

Pure zero resistance would prevent electric fields from entering a block of superconductor (the change in magnetic fields will induce eddy currents) to counter any change in the local magnetic field) and this effect is called perfect diamagnetism.

The Meissner effect is different: it's a phase change effect -- it takes energy to expel the magnetic field. If the magnetic field is strong enough, the material may never superconduct. In any case, the transition temperature T_c is actually a function of the local magnetic field.

Furthermore, if you boost the field enough, you can quench the superconductivity and initiate resistance heating -- it can get nasty with high currents. Is the magnetic expulsion perfect? Sometimes it is, and sometimes not, because of flux pinning.

Since we often want to use superconductors to either make high magnetic fields (like in magnetic resonance imagers) or to carry large currents (that induce high magnetic fields) the Meissner Effect, and the magnetic dependence of the transition temperature are important considerations for practical superconductors.

Pure zero resistance would prevent electric fields from entering a block of superconductor (the change in magnetic fields will induce eddy currents) to counter any change in the local magnetic field) and this effect is called perfect diamagnetism.

The Meissner effect is different: it's a phase change effect -- it takes energy to expel the magnetic field. If the magnetic field is strong enough, the material may never superconduct. In any case, the transition temperature T_c is actually a function of the local magnetic field.

Furthermore, if you boost the field enough, you can quench the superconductivity and initiate resistance heating -- it can get nasty with high currents. Is the magnetic expulsion perfect? Sometimes it is, and sometimes not, because of flux pinning.

Since we often want to use superconductors to either make high magnetic fields (like in magnetic resonance imagers) or to carry large currents (that induce high magnetic fields) the Meissner Effect, and the magnetic dependence of the transition temperature are important considerations for practical superconductors.

How is this different from that other metal that shrinks when heated, Nitinol? It's only from 1932, so I don't expect THAT to get in the way of the editiors...

of who can link the most websites about holograms...cause i just won!

The holoshop

another page

yahoo group on holography

the big holobook

how to shoot holograms

holoworld

silver holographic

holophile

the last one but a good one

The slashdot article just talks about using ballons as resonant chambers - the speaker elements are included.

What about an inflated piezoelectric film ballon emitting a perfect spherical sound wave...
The Interactive Balloon
DIY example - make your own

Update: Images Company has those Nitinol wires by the foot.

Update: Images Company has those Nitinol wires by the foot.

Nitinol is made from Nickel and Titanium, and changes its shape based on applied current (well, "Ohmic Heating", actually). A search on Google turned up such cute examples as this.

It doesn't seem strong enough for large-scale use, but it does show proof-of-concept nicely.