Archivist

The archivist is a base class from the Heroes of Horror book. This class is similar to a cleric in its practice of Divine Magic and faith. However, the archivist does not use the power of the divine in the same manner as a cleric. Instead the archivist uses a faith in knowledge to channel the divine. Similar to the wizard, the archivist must carry around a "prayer book." This is similar to a spell book in that it contains the knowledge and power that archivists have amassed for themselves through study and travel. In essence this seems to be a standoff version of the "Cloistered Cleric" variant, which was essentially a cleric that spent most of its time studying and lost melee potential for bonus skills (i.e. Knowledge (all).)

Combat
The other notable difference of the archivist is that it does not use divine magic and fight in melee instead it leads and directs combat from the back by providing information on the types/qualities/weaknesses/strategies of the parties foes. An archivist can use their acquired knowledges to give bonuses to the party for individual fights. These temporary bonuses usually grant bonuses to hit, damage, saves as per normal with most such abilities/spells. By epic level an archivist will have "studied" almost all types of creatures in a setting and will be well prepared to direct combat against almost any foe in nearly any terrain or situation.

Alignment
Archivists are not tied to any aligned in the same way that a cleric is not tied to any alignment. They can follow whatever morals they choose in general but most are about the same alignment as their patron deity.

Heroes of Horror Wizards of the Coast: http://www.wizards.com/default.asp?x=dnd/ex/20051007a&page=3