Ascetic Mage( Complete Adventurer, p. 105)
You practice an unusual martial art that mixes self-taught spellcasting and melee attacks to great effect.
Improved Unarmed Strike (PH) , ability to spontaneously cast 2nd-level arcane spells,
As a swift action that doesn't provoke attacks of opportunity, you can sacrifice one of your daily allotment of spells to add a bonus to your unarmed strike attack rolls and damage rolls for 1 round. The bonus is equal to the level of the spell sacrificed. The spell is lost as if you had cast it. If you have levels in sorcerer and monk, those levels stack for the purpose of determining your AC bonus. For example, a human 4th-level sorcerer/1st-level monk would have a +1 bonus to AC as if she were a 5th-level monk. If you would normally be allowed to add your Wisdom bonus to AC (such as for a unarmored, unencumbered monk), you instead add your Charisma bonus (if any) to your AC. In addition, you can multiclass freely between the sorcerer and monk classes. You must still remain lawful in order to continue advancing as a monk. You still face the normal XP penalties for having multiple classes more than one level apart.