I know it's possible for Oculists and Telepaths to work together to make controlling  demonic servants easier but would any of the following combo's work as well? 

A Telepath and a Mystic working to read someone's mind or control someone from afar. 
Alteration Wizards and Necromancers to both make the corpses less recognizable or better "equipped" for their new task.
A Mystic helping a Planar Mage to find the right formula's
A Mystic and An Alchemist to find the best ingredients. and finally Alchemists boosting the power of Destruction Mages with poisons and flamable oils.

Of course there are many more combinations possible, these were just the ones I could think of.