I'll give a shoutout too Hy. It removes the Python interface, and replace it with a LISP interface.
The neat part is that its currently compatible, and bidirectional, with 2.6, 2.7, 3.2, 3.3 and pypy.
We even added a few steps so we will have support for 3.4!
I really hope Hy catches on as the way to add DSLs to Python projects. I did this to one of my small projects and I'm very happy with the results: http://pyzmo.readthedocs.org/en/latest/#usage-hy
I have been toying with hy for the last two months and enjoying every minute. It is a very strange feeling when you are able to use the batteries-included of Python with the simple syntax of a LISP (nothing against Python's syntax). The documentation is fairly good, and library support is surprisingly good. I'm planning on using it for a very small web app (with Flask).
https://github.com/hylang/hy
It's a great example of how Python isn't that different from LLVM and JVM!