URIs for organizations

Can anyone point to prior art or emerging standards for identifying 
organizations with URIs?   I want something as unambiguous as CAGE codes 
[1] or DUNS numbers [2], but I would like to use URIs in a namespace 
that carries some weight as a recognized standard.  Alternatively, I 
could use standard Properties that meant "CAGE code" or "DUNS number", 
each of which would have the appropriate set of codes as its range.

Thanks,
--Paul Tyson

[1] http://www.dlis.dla.mil/CAGEserv.asp
[1] http://www.dnb.com