The instructions in the wiki for making frozen yeast cultures is great stuff... this is referring of course to the glycering mixture process with test tubes.
However, instead of washing the yeast cake, is there any reason you couldn't just use the thick slurry in the bottom of a starter jar to produce the test tubes in this case? It would seem easier to maintain sterility, and easier to get a good hearty quantity of yeast that way.
Has anyone tried this? I'm thinking if you just take the 1st generation yeast that you've built up in a starter, and make four tubes out of it (for example) it would be a quicker process than washing/separating/pipetting/washing/separating/pipetting that is part of the wiki process.