Whoops, my bad! Definitely should've included an example. I don't have anything specific in mind yet but this was the inspiration. Sorry, I meant a nerf gun that normally plugs into a USB port on a larger machine.
Far-seeker:
Attach the data lines (see here) to either the 'scope or probe so you can read the signals being sent. Then plug the modified cable into your computer, start up the program used to control the nerf gun, and finally record the data pulses associated with each specific command sent by the program.
Thanks a ton for that. Would it be as simple as outputting a certain number through the data lines to the gun or would you expect it to be more difficult than that? I'm guessing it depends on the design of the nerf gun but I'm not sure if there's a standard used for this purpose or not.