Pretty much useless without a kiln and a lot of time.... Much easier to make friends with someone who makes fired clay stuff. Personally, I have friends at the "London Clay Arts Centre" where they have a large kiln.
Generally not worth the time to make them custom when you can buy stuff just as cheap at the store and paint it a little yourself.
Agreed that the 20' rule takes president, and generally the less time and effort the better.
It takes DAYS to fire pottery.