[Tcl] has a distinguished record of accomplishment in supporting [architecture]s based on the publish-subscribe [pattern]. One prominent domain is [process control], where [CPU] bound Tcl to Tibco and MQ [middleware], as well as a home-grown publish-subscribe bus. CPU's current owners apparently have "buried" all these products. Apparently XMLblaster [http://www.xmlblaster.org/] still lacks a demonstration client in Tcl as 2004 begins, although someone (? Benno Lange?) was working on it. It '''ought''' to be straightforward ... [Tuplespace] is a publish-subscribe mechanism, one with at least a couple of distinct advantages, including the ease with which one can register interest in a ''pattern'', and not just a variable. ------- The "msg" [http://cfa-www.harvard.edu/~john/hacks/msg] interface that is used to operate F5 instrumentation at the MMT Observatory. [JBR] [[Explain how [Tequila] can be regarded as publish-subscribe.]]