I am a C++ developer, slowly getting into web development. I like LISP a lot but don\'t like AllegroCL and web-frameworks available for LISP. I am looking for more freedom and a
I am a Pythonista; however, based on your requirements, especially the "cool hacks on the language level", I would suggest you work on Ruby. Ruby is more flexible in the Perl way and you can do a lot of hacks; Python is targeted towards readability, which is a very good thing, and generally language hacks are a little frowned upon. Ruby's basic types can be modified in a hackish way that typically prototype languages allow, while Python's basic types are more suited for subclassing.
By the way, I would add a minor correction: both Ruby and Python are very, very object-oriented, and neither is intended to be used for quick-and-dirty scripts the Perl way. Among the two, Ruby is syntactically more similar to Perl than Python.