Using multiple programming languages or paradigms, while implementing software solutions, are not uncommon anymore. For example, many of us definitely have been using C#, SQL and Scripting languages to implement applications. Composing multiple programming languages to build solutions, polyglot programming, is in practice for a while.  We can extend this paradigm further with the more powerful, yet simple, ways of mixing Dynamic Languages Runtime (DLR) based programming languages like IronRuby and IronPython as well.

Here are a few links:

Mixing And Matching Languages

First Look at IronRuby

IronRuby Home Page

Dynamic Language Runtime (DLR)