Cleric/Mage mixes

[Nonlethal Force]

Cerebromancer is what you are looking for from the XPH

 

[MatthewJHanson]

There is also the Mystic Theurge variant for Psion/Mage's. Mystic Psion? I forget the name. It's in the XPH

Cerebremancer.

There's also a Psychic Theurge on the Wizards website, which combines psion and cleric.