Here's how I write Python programs on the N900 on my Mac

  1. installed the ssh package, open ssh server
  2. via ssh, I use terminal.app to the ip address of the N900 (which I can see at all times with the personal IP address widget) and test stuff out interactively using python's command line interpreter, aka the python REPL
  3. when i am happy with the code that I have tested the REPL, I add it to the file on the N900 which I edit on emacs running on my mac using ange-ftp
  4. test the code out on the n900 from terminal.app, 90% of the time it just works since I tested it in the REPL unlike my C/C++ days when something you never thought of always required you to re-compile

Easy, peasy. No need to learn silly :-) Java or C+ or wait for compilation and access to the full power of your Mac for google searches plus you can execute on the N900 directly. No need for silly :-) emulators which in my experience aren't very useful.