Feat or something I can't remember

[VolcanicErupt]

I was looking through books the other day and I can't remember what book or what it was, but I remember I wanted it for my Sorcerer because she has Fast Healing. It was something about cutting or stabbing yourself and you get the use of a Metamagic feat. It was obscure and I liked it. Please help me find it!

[flappeercraft]

Don't know of any feat that does that but the Tainted Scholar (HoH) and Tainted Sorcerer (UA) PrC's get something similar but the damage is constitution damage rather than HP damage.

[Zaq]

Don’t have my books open so I’m going from memory, but have you looked in the magic item set section of MIC? I recall there being an item set geared towards spontaneous casters that involved doing damage to yourself. Forget what it actually does or if it’s any good, mind you, but maybe it’s what you were thinking of?

[Thurbane]

Don’t have my books open so I’m going from memory, but have you looked in the magic item set section of MIC? I recall there being an item set geared towards spontaneous casters that involved doing damage to yourself. Forget what it actually does or if it’s any good, mind you, but maybe it’s what you were thinking of?

Good call - Instruments of the Blood Gift (MIC p.202). Doesn't do exactly what the OP is saying, but may be what OP was thinking of...

The Blood Magus PrC (CAt p.26) also has a few abilities along a similar theme.

[OgresAreCute]

The Tainted Scholar PrC from Heroes of Horror has an ability called Blood Component, which lets you poke yourself for 1 damage as a free action to make a spell you're casting have +1 caster level.

[ShurikVch]

The Tainted Scholar PrC from Heroes of Horror has an ability called Blood Component, which lets you poke yourself for 1 damage as a free action to make a spell you're casting have +1 caster level.Tainted Sorcerer (http://www.d20srd.org/srd/variant/campaigns/taint.htm#taintedSorcerer) can use blood in place of costly material components
Same thing with OA Maho-Tsukai

Eldritch Corruption [tainted] feat (Heroes of Horror)
Reserves of Strength (Dragonlance Campaign Setting) - if you're immune to Stunning

Also, if the character in question is Vampire - Lifedrinker PrC (Book of Vile Darkness) - Spell Boost CF