Nancy LC provided the link to what I have found to be the best discussion. --------------------------------------------------------------------------------

"http://amath.colorado.edu/~baldwind/sous-vide.html

Another web page."

Also, there is a company called Auberins that sells a "PID temperature controller" for $122.50 that is designed to work with a crock pot or rice cooker that does NOT have digital controls. I talked my son (aerospace engineer and gadget freak) into buying me one for Christmas. I have used it successfully to cook tender, juicy pork loin slices. You need to have a vacuum sealer that uses plastic bags or rolls of material that are made to be boiled or microwaved. One brand is "Flavor Saver", but there may be others cheaper. One of the things I like about it, but haven't tried yet, is that you can pasteurize eggs in the shell. They can be used in any recipe that calls for uncooked eggs, but don't carry the risk of salmonella. See the link Nancy LC provided - the info is several pages in.