[volt-nuts] Is there a "standard" much better than a LTZ1000, but much cheaper than a Josephson Junction Array?

[Dr. David Kirkby (Kirkby Microwave Ltd)]

The question about the Josephson Junction Array got me thinking. I wonder
if there are any sort of technologies that can produce a voltage with much
better stability than the LTZ1000, but without the cost of a Josephson
Junction Array. A sort of half-way house.

BTW, I see some rather battered up LTZ1000A's on eBay,

http://www.ebay.com/itm/1x-LTZ1000ACH-Ultra-Precision-Reference-LTZ1000A-/111325506311

that have dents in them. They are more expensive than buying the chip new
from the Linear Technology website.

http://www.linear.com/purchase/LTZ1000

Yet people seem to buy them. Now I know the stability of those improve with
age, but when they have dents in them, its clear they have not been exactly
cared for. Maybe I will buy some new LTZ1000As and stick them on eBay for
$100 and see how many I sell !!

It seems the real cost of an LTZ1000A standard is not the chip, but the
resistors you need.