Ever played Space Invaders (or, failing that, remember when SethBling created a version of it)? Jesper the End remembered, and wanted to create a fully working version of the game, playable inside Minecraft. This is the result of his labors! You can , but you will need the recent Snapshot to do so (14w02c). Enjoy!
That seems like a very complex machine, do you have any other machines like it? Ones that serve different purposes? Its a good thing that you have a downloadable world for others to use, because I'm not sure just anyone could build it! What servers do you play on?