Cross-platform command line tools

I have a hobby of creating small command line utilities that are cross-platform (Windows, Mac, Linux). For this I use Python with a she-bang line for the Mac and Linux platforms, and adding a bat-file script as disguise in Windows. It's quite fun to do and I thought maybe someone else would have the same obscure hobby? Anyways, I just created a blog to write about my small scripts (in elementary fashion, suitable for the complete novice to start hacking) at http://portablecommandline.blogspot.com/. Feel free to have a look and drop me a comment (just one script so far, but I promise to post more shortly!).

A couple of questions:
a) Who are persuing the same hobby?
b) What scripting languageus do you employ for cross-platform hacking?
c) Any ideas for great cross-platform CLI utilities?