It's a PrC, but the Wyrd from Half Orcs (BadAxe Games) is a Barbarian/sorcerer multiclass build.
d6 HD, Average BaB, Good Fort/Willsaves, Poor Ref saves, offset spellcasting (gains an effective level every other level), 4 skill points per level.
Storyline is that the Wyrd is destuctively empathic. Every time you are charged, a character/npc begins raging near you, you are approached by a raging character/npc, or enter a rage yourself you gain a rage point (as I intrepret the class, you can't NOT receive these rage points). You can spend the rage points to increase caster level, add metamagic feats, decrease spell casting time with a metamagic feat, etc.
You can only spend your Cha bonus worth of rage points in a round. AT the beginning of your next action, if you have too many rage points bad things happen (might hurt just you, might kill everyone around you). The book comes with an Enraged Casting Feat: Concentration check to cast during a rage (DC 15 + spell level; +5 to cast defensively). Spell casting time doubles.
The book also has other rage based feats, including one that gives the bonuses of the Power Attack, Cleave, and Great Cleave Feats. The catch: It takes up two uses of your rage per day, and you have to move to and attack (charging if nessecary) the closest target, even if it is a friend. Attacks have to be full attack actions, if possible. The feats help you make for what you lose taking levels as a sorcerer.
Flavor text has warchiefs tying Wyrds to a bier, surrounded by a raging horde. Can you guess how it turned out?
