As we don't really have to many "insane weapons" I figured this would be a nice one.
For starts, just by clicking you do a "punch" animation (Like the Heavy TF2 fist mod thing).
But if you hold the left mouse button down for more than a second and release, orange particles come out of the player's hand when it punches and the classic "FALCON PUNCH!" sound is played.
This can easily be accomplished, but because I have no idea how to animate, I'm leaving this to someone else that is more capable.