In this case an engine mod would most likely be the way to go, however (inefficient) methods could be used in torque script.
Now it [the beam gun] just depends on Badspot implementing such a thing or Space Guy following up on his statements that it could be done in torque script.
@ beachbum, there aren't any real laser shooters, they might be a blank bullet with some particle effects sure, but no actual "touch any part of the laser to get hurt" lasers. Just projectiles with laser effects.