The NIST Identifier Collaboration Service or NICS, was a general-purpose registry for identifiers, implemented in Tcl, and designed in part to be used to manage resources such as namespaces within Tcl.
[http://www.mel.nist.gov/msidlibrary/doc/usenix.htm%|%Managing Tcl's Namespaces Collaboratively], [Don Libes], 1996: