It's been replaced by dbus. Which does indeed have strict types and other features that might be desirable (multicast?). You raise an interesting idea: A shell that pipes materials around from process to process through dbus, and a set of command line tools that accept input over dbus.

http://en.wikipedia.org/wiki/D-Bus does not work for IPC between computers, AFAIK, only for processes within one machine. CORBA works across machines.

It was terrible on multiple levels and deservedly faded away after a short fad.

And this:

http://google.com/search?q=xml-rpc

Still being used some.