Non playable but the invaders move and make sounds, and the red spaceship has its "siren" too!
I've just uploaded a python tool for downloading cartridges :D
Right now you use it like this:
$ p8dl 10022
But, in a future, I'd love it to be able to browse cartridges like Voxatron does.
It should work in Windows, OS X and Linux.
Check it out with
$ pip install p8dl
The code is here: https://github.com/franciscod/p8dl
What do you guys think?