How is it possible to become self-sufficent in yeast for baking ?

I'm trying to become self-sufficient in bread yeast, not having
to rely on the availability of dried bread yeast from the shops,
or buying a ball of yeast from the health food store. I'm not
sure what you call the yeast sold in non-dried form... it's like
clay/putty.

For brewing beer, I'm self-sufficient in yeast. I preserve
yeast in glycerine and freeze. Or, I keep slants of yeast on
agar. Or, I re-culture beer yeast from the bottom of a bottle
of beer. Or, I keep a yeast supply in a sucrose solution.

Is it possible to keep a good dual-purpose yeast, capable of
producing a decent beer and bread ? Older textbooks talk
about using the same yeast for beer and bread, but the newer
materials usually adopt a consumerist and specialist approach
to brewing and breadmaking. In other words, buy your beer
yeast from the beer brewing shop, and buy your bread yeast
some other store. Doesn't make any sense to me.

Crossposted to rec.crafts.brewing.

Look forward to reading your enlightening comments.

d