I see a Harmony cartridge in your VCS. For those, who don't know, that device makes developing on real hardware pretty easy and fun.
Emulators are very solid, however, if one is pushing it, or wants to test the variations on original hardware out there, a Harmony cartridge makes a lot of sense.
(just read your page some, and see you mention Harmony explicitly)
You've done a great job boiling something hard to understand and conceptualize down to the very basics in true Atari 2600 style! Few systems offered such a broad range of potential experiences, variety of controllers, color, sound, types of games possible, coupled with a seemingly useless 128 bytes of RAM.
Over the years, I've been amazed at how that combination, and the iconic nature of the game console, drive people to boil things down to their essence, and keep it fun.
There really is nothing else like it.
Now I'm off to play your game on my machine. :D