Here's some new ones I'd like commented on:
Impaling: This potent and feared ability allows the weapon to pierce the hearts of those it strikes. Upon a roll of natural 20 (followed by a successful confirmation roll), the weapon pierces the opponent's heart (if it has one). Some creatures do not have hearts. Others, such as undead other than vampires, are not affected by damaging its heart. Most other creatures, however, die when their hearts are impaled. An impaling weapon must be a piercing weapon.
Strong necromancy and transmutation; CL 18th; Craft Magic Arms and Armor, circle of death, keen edge; Price +5 bonus.
Variable Energy Burst: Upon command, a variable energy burst weapon is sheathed in acid, cold, electricity, fire, or sonic energy. The energy does not harm the wielder. The weapon deals an extra +1d6 damage of the selected type with each successful hit. In addition to the extra energy damage, a variable energy burst weapon deals an extra 1d10 points of energy damage of the selected type on a successful critical hit. If the weapon's critical multiplier is X3, add an extra 2d10 points of energy damage of the selected type instead, and if the multiplier is X4, add an extra 3d10 points of energy damage of the selected type. Bows, , crossbows, and slings so crafted bestow the selected energy upon their ammunition.
Strong evocation; CL 12th; Craft Magic Arms and Armor, weapon of energy; Price +3 bonus.
Impacting: Upon command, an impacting weapon readies itself to bash into its target. An impacting weapon deals an additional 1d6 points of bludgeoning damage on a successful hit. Bows, crossbows, and slings so crafted bestow the blunt force upon their ammunition.
Moderate transmutation; CL 10th; Craft Magic Arms and Armor, bull's strength; Price +1 bonus.
Cuncussive: A cuncussive weapon functions as an impacting weapon that also explodes with crushing force upon striking a successful critical hit. In addition to the extra bludgeoning damage from the impacting ability, a cuncussive weapon deals an extra 1d10 points of bludgeoning damage on a successful critical hit. If the weapon's critical multiplier is x3, add an extra 2d10 points of bludgeoning damage instead, and if the multiplier is x4, add an extra 3d10 points of bludgeoning damage. Bows, crossbows, and slings so crafted bestow the blunt force upon their ammunition. Even if the impacting ability is not active, the weapon still deals its extra bludgeoning damage on a successful critical hit.
Moderate transmutation; CL 12th; Craft Magic Arms and Armor, bull's strength; Price +2 bonus.