I just decided that I want to be able to shoot stuff out of a pneumatic cannon by calling/texting a phone.
After a quick google, it looks pretty easy to use a cheap prepaid phone as a remote detonator, and I think this would be a cool way to do it.
If you want multiple barrels, or shots, it should be fairly straight forwards to set custom ringtones to different cell numbers and use an arduino to analyze the signal then fire the tube. Actually, an even better way would be to have an arduino that sets off a tube for each text it receives. In case you are wondering how the phone communicates with the circuit, you just remove the vibrator from the phone and use those leads.
If you are interested in one of these for yourself, pay me for parts, shipping, and labor and it's yours.
I can also sell modded prepaid phones if you want to use them for another purpose, but keep in mind I don't have any stocked and I haven't attempted making one for myself yet, so you might want to hold off on ordering until I make one for myself
Boring but necessary disclaimer that you will probably read even though I already told you it is boring (I always read the fine print, too ): I am not responsible for anything you do with these devices. Use the devices at your own risk.