## Other Kvass varieties

You can make kvass using sauerkraut juice as basis and beets for
flavoring.  It's marketed as probiotic drink, so I dunno.

## Sourdough bread

It would be neat to no longer need to buy bread (instead you buy
equivalent amounts of flour).  Seems to be easy as everyone's doing it
during quarantine.

## Yogurt

Why not?  You need yogurt to make yogurt though.  That bootstrapping
issue is something worth looking into.

## Kefir

Requires special kefir grains.  Exotic!

## Kombucha

Another exotic choice.  The bacteria make me uneasy though, people
managed poisoning themselves with it.

## Cider

This takes a lot of time, a cellar and special equipment.  So nothing
for my apartment.  A shame, I enjoy the apple flavor (which is most
likely artificial anyway).