These feats are inspired by Hiroki Samura's manga Blade of the Immortal . It's released in the U.S by Dark Horse and is worth checking out.

FLIGHT OF THE GOLDEN WASPS (General)
Prereqs: Ambidexterity, Rapid Shot
Curtain of Death! Flight of the Golden Wasps!!!
This feat allows one to throw a hail of blades at her target. Using a throwing weapon of small size or smaller, she may make an extra amount of ranged attacks equal to her dexterity modifier, to a maximum of eight (four weapons in each hand), including her normal attacks. For a small weapon, the maximum is four.
For each weapon past the normal limit thrown, a cumulative -2 penalty to hit is applied. Example: Rin, a 12th level fighter, throws 5 daggers. She has 3 attacks normally, so the progression goes like this 12/7/2/0/-2
When this feat is used, the user throws her blades in a cone with a diametre equalling the weapon's range. Due to the fact that this attack requires the user to lose inhibition during the moment of attack, she is winded for the next round.

12 BLADES (General)
Prereqs: Quick Draw
The sight of someone casually reveal a virtual armory of weapons on his person tends to be unnerving. With this feat, the user may reveal a number of weapons, maxing at 1/2 his level, as a full round action. For that round he gains a bonus to intimidation checks equal to the number of weapons shown.

DESTRUCTION TESTING (General)
Prereqs: Toughness, Endurance, Con 16 +
"Been...a long time...ages...since somebody...punched a whole in the old brainpan...heh...eyesight's sorta...cloudy, but...doesn't hurt as much as a stab through the guts. Weird, huh?"
"Well...uh...crap. Think I better run...
The perverse tenacity of a truly determined adventurer can quite frankly scare the piss out of a less experienced foe. This feat allows the sheer endurance of an opponent against brutal punishment to terrify his enemies.
Each time a character with Destruction Testing is dealt a critical hit and survives, he may make an intimidation check as a free action, with a DC equal to 10+damage dealt by the critical hit. Any enemy within 30 ft and who saw the hit dealt must make the check. Failure indicates that the foes are demoralized, and they suffer a -2 penalty to attack rolls and AC for 1d4 rounds.

BLOOD OF A THOUSAND
"Quit Squirming around! You've been stabbed through the guts! ACT LIKE IT!!"
Prereqs: Barbarian's Rage Ability, Great Fortitude, Iron Will, Destruction Testing, Damage Reduction (Any)
This feat allows a character's rage to make him a veritable war machine, plowing through enemies like they were nothing, shrugging off blows like an iron golem.
Whenever the character is damaged in combat, he may make a will check DC 10+damage dealt. If he succeeds he ignores the damage. This can only be used during the Rage ability. However, when the rage ends, all the damage ignored by this feat is dealt back again. An additional point of damage is applied for each wound, and the character must make a fortitude check (25) or be counted as bleeding until healed. If the character fails a will saving throw from the damage, the effect ends, the damage is dealt to the character, and his rage ends.