Haha, very nice! I like the attachment idea, fits the theme very well. I did find a way to cheese it though: if you can get two of the attachments that fire the beams from each side, you can just spin around in circles very quickly and destroy pretty much everything without even trying. A simple way to fix that might be to limit how quickly the player can spin. One other suggestion would be to lock the cursor somehow. I kept running the cursor of the screen and losing control. Playing in full screen would fix that but it's maybe still something to keep in mind.
Super cool little game, I like it a lot!