Since this board seems to be for weapon ideas...
The Sonic Canon uses focused sound to inflict damage on targets. Being as the damage mechanism is SOUND, the weapon's performance is very much dependent on what medium it's shooting through. And while technically an energy weapon, the Sonic Canon has the distinction of producing less heat than any other energy weapon barring a small laser.
Sonic Cannon
Tonnage: 6
Crits: 3
Heat: 1
-------Medium---------
Air Water Vacuum
Damage 10 15 15
Range 4/8/12 6/12/18 Melee
Note: In a vacuum, there is no medium through which sound can propagate, so a Sonic Cannon can only be used by putting the muzzle right up against the target and firing.