It also works with Half Life 2 and other Source Engine games.
Just throw the melon at the thing that you want the effect applied to.
melon command generator
ent generator
None Health Model Scale Gravity Base Velocity Render Mode Render FX Fade Min Distance Fade Max Distance Angles Render Color Friction Mass Scale Explode Damage Explode Radius None Health Model Scale Gravity Base Velocity Render Mode Render FX Fade Min Distance Fade Max Distance Angles Render Color Friction Mass Scale Explode Damage Explode Radius None Health Model Scale Gravity Base Velocity Render Mode Render FX Fade Min Distance Fade Max Distance Angles Render Color Friction Mass Scale Explode Damage Explode Radius Replace Model Path Generate Command