I've started experimenting with slants and have tried my first batch. I really think this is the best way to go as far as saving yeast is concerned. As far as I'm concerned the best article on the web is http://www.realbeer.com/spencer/yeast-culturing.html
(New to posting, not sure I posted links right.)
This article explains in laymens how easy it is to culture yeast with some test tubes, some geletin and DME. By culturing from a original generation, in other words a tube of white labs or smak pak, not slurry, a life time of never ending yeast supply is assured. After three months when the yeast has used up the DME an old slant can reculture new slants. With agar, the yeast hasnt made enough copies of itself to mutate like it can reusing slurry.
I do have a few issues with the article. Spencer writes, due to amount of DME and yeast the corks in test tubes may loosen during first week of room temp. culturing. Guess what, they explode off the test tubes twice daily! I had to throw away my first batch due to contamination concerns since tubes were open after corks flew off. Some times at night I would hear POW, then in the morning corks on the floor. After a week or so the yeast slows down and the corks stopped flying off. then slants can be put in refridgerator, wrapping the corks in electrician tape.
For my next batch I am going to try putting in sterile cotton balls in tubes instead of corks for the first week at room temp. Airlocks arent going to work on test tubes.
If any one has had tried slants let me know your experiences.