A number of years ago, much to my wfe's chagrin, I purchased a 1960's era Civil Defense issue geiger counter. It was only $15, so what the heck, right? Well with events transpiring in Japan, I thought it might be fun to wire the counter to the web. So, you can see it at http://geiger.bahneman.com. Seattle's only live geiger counter online. It is a pretty rough site, but it does work. I'd like to add an automatic way to count the ticks using some sort of audio analysis, but by the time I did it, interest will have passed. 

Check it out: http://geiger.bahneman.com