I am looking at this too. I remember, back at school, my most fun programming assignment was making a complier for a simple interpreted language. The compiler was done with this language whose file extensions ended up with .py .

After graduation, and working for years in companies that used Java, I still had good memories of that very powerful language, and I dreamed one day would be able to program with it again..

Well, I still have to code in java for living, so, my next home assignment is writing a python interpreter in java, (J2ME to be more exact).