I'm putting this up in response to Cranewings Weapon Customization Thread. I made this a while back, and I feel that it is pretty self explanatory. If there are any questions, feel free to ask.
Simple; Light Melee
Cost: 4 gp
Damage: 1d4
Critical: 20/ X2
Special: none
Optional (Choose one): Thrown (20ft range), Non-lethal, High Threat (19-20/ X2), High damage, Monk, Trip, Disarm
Simple; 1-handed Melee
Cost: 8 gp
Damage: 1d6
Critical: 20/ X2
Special: none
Optional (Choose one): Thrown (20ft range), Non-lethal, High Threat (19-20/ X2), High damage, Monk, Trip, Disarm, Brace
Simple; 2-handed Melee
Cost: 12 gp
Damage:1d8
Critical:20/ X2
Special: none
Optional (Choose one): Thrown (10ft range), Non-lethal, High Threat (19-20/ X2), High damage, Monk, Trip, Disarm, Double (1d6/1d6), Brace, Reach
Simple; Ranged
Cost: 35 gp
Damage: 1d6
Critical: 20/ X2
Special: Range 80 ft.
Optional (Choose one):High Threat (19-20/ X2), High damage, Better Range (120 ft.)
Martial; Light Melee
Cost: 10 gp
Damage: 1d4
Critical: 20/ X2
Special: none
Optional (Choose two): Thrown (20ft range), Non-lethal, High Threat (19-20/ X2), High damage, Monk, Trip, Disarm, High Crit. (X3)
Martial; 1-handed Melee
Cost: 20 gp
Damage: 1d6
Critical: 20/ X2
Special: none
Optional (Choose Two): Thrown (20ft range), Non-lethal, High Threat (19-20/ X2), High damage, Monk, Trip, Disarm, High Crit. (X3), Brace
Martial; 2-handed Melee
Cost: 30 gp
Damage:1d8
Critical:20/ X2
Special: none
Optional (Choose two): Thrown (10ft range), Non-lethal, High Threat (19-20/ X2), High damage, Monk, Trip, Disarm, Double (1d6/1d6), High Crit. (X3), Brace, Reach
Martial; Ranged Missile
Cost: 70 gp
Damage: 1d6
Critical: 20/ X2
Special: Range 80 ft.
Optional (Choose Two):High Threat (19-20/ X2), High damage, Better Range (120 ft.), High Crit. (X3)
Exotic; Light Melee
Cost: 10 gp
Damage: 1d4
Critical: 20/ X2
Special: none
Optional (Choose three): Thrown (20ft range), Non-lethal, High Threat (19-20/ X2), High damage, Monk, Trip, Disarm, High Crit. (X3)
Exotic; 1-handed Melee
Cost: 20 gp
Damage: 1d6
Critical: 20/ X2
Special: none
Optional (Choose Three): Thrown (20ft range), Non-lethal, High Threat (19-20/ X2), High damage, Monk, Trip, Disarm, High Crit. (X3), Brace
Exotic; 2-handed Melee
Cost: 30 gp
Damage:1d8
Critical:20/ X2
Special: none
Optional (Choose Three): Thrown (10ft range), Non-lethal, High Threat (19-20/ X2), High damage, Monk, Trip, Disarm, Double (1d6/1d6), High Crit. (X3), Brace, Reach
Exotic; Ranged Missile
Cost: 70 gp
Damage: 1d6
Critical: 20/ X2
Special: Range 80 ft.
Optional (Choose Three):High Threat (19-20/ X2), High damage, Better Range (120 ft.), High Crit. (X3)
Basic Amunition
Cost: 1 GP/20
Optional: None
Advanced Ammunition
Cost: 5 GP/20
Optional (Choose one): Better Range (+20 ft), Blunt (deals Bludgeoning damage, can deal nonlethal)
High Damage: Increase damage by one step.
Brace: If you use a readied action to set a brace weapon against a charge, you deal double damage on a successful hit against a charging character (see Combat).
Disarm: When you use a disarm weapon, you get a +2 bonus on Combat Maneuver Checks to disarm an enemy.
Double: You can use a double weapon to fight as if fighting with two weapons, but if you do, you incur all the normal attack penalties associated with fighting with two weapons, just as if you were using a one-handed weapon and a light weapon. A double weapon can be wielded as a one-handed weapon, but it cannot be used as a double weapon when wielded in this way—only one end of the weapon can be used in any given round.
Monk: A monk weapon can be used by a monk to perform a flurry of blows (see Classes).
Nonlethal: These weapons deal nonlethal damage (see Combat).
Reach: You use a reach weapon to strike opponents 10 feet away, but you can't use it against an adjacent foe.
Trip: You can use a trip weapon to make trip attacks. If you are tripped during your own trip attempt, you can drop the weapon to avoid being tripped.
I'm probably going to mix this with what I wrote to be the ultimate house rule weapon system :)
Cool.