I got my T34 and Panther last week. I already made a mod. Using a voicemail greeting card.
I wanted to add a gun blast while firing... so i did

You'll be able to record your own gun sound with this and trigger it with the controller.
Works perfectly! Adds a lot of exitement to the battle

(disclaimer)
If you try to do this you will need some electronics experience. Don't blame me if you fry the controller.