how to build a cold smoker

I'm very interested in pictures and videos of cold smokers.  And stories of how they are build, how they are used.  Maybe pictures/stories of finished products?  How long should the meat last?

Here is a short video with a cold smoker and, oddly enough, a composting toilet.

Here is a link to a home made design:

http://cowgirlscountry.blogspot.com/2008/01/building-cold-smoker-smokehouse.html