Tcl is one heck of a Swiss-army knife solution. The core team is of the first order. The best thing is that it's so easy to use pipes to integrate a 'C'/C++ console mode program and control it via stdin/stdout/sockets. That turns out to be a significant architectural plus - rather than using some MVC C++/Java type library, you get complete seperation of concern. You don't even have to integrate it tightly with 'C' code; just use stdin/stdout and wrap a Tcl package to build a pipe around it.

Tcl might have been too easy. I also recall ESR dismissing it at one point in favor of Python.