Peter Norvig has some good posts about building a small lisp in Python: http://norvig.com/lispy.html and http://norvig.com/lispy2.html

Doing those exercises in Javascript (which I'm very familiar with and has better functions than Python, IMO) really helped me understand compilers, and lisp better. Lisps are awesome, and I've been picking up a lot of Clojure lately. Love it, and never want to go back.

Probably I will go a bit off-topic, but as a person, who is more familiar with python than any other programming language, what functions JS has, which are "better"?

The only thing I could think of at the moment is that JS gets lambdas right.

Neat post, though I'm a bit disappointed it didn't go into infix to postfix conversions.