So aside from User Interface, I also created the signature weapon for Palladium Absolution, the Force Gun.
This weapon is a simple physics weapon, with a primary and secondary fire mode
The primary fire mode is a single target fling, throwing enemies from one side of the map to the other with one shot.
Then we have an Area of Effect fire on the secondary, a smaller range, less powerful knock back centered on the player knocks all nearby enemies back out of attack range

Using InstantHitMomentum in UDK allows the single target fire to blast individuals away with extreme force.

And this shows the projectile fire, the AoE mode for this weapon, there is no direct damage done, however the radius and MomentumTransfer allow a large knock back over a specified area. The lifespan of this projectile is how it is centered on the player, causing the projectile to explode almost as soon as it is fired.