Wizard Arcane Build
This is a fun build I made based around the idea of using all arcane spells with Temporal Flux, Arcane Dynamo, and Prodigy to:
A) Keep enemies constantly slowed by your attacks.
B) Easily regenerate arcane power while building up Flash of Insight for an extra powerful finishing attack.
The best way to use this I found was to instantly cast Hydra which will slow down enemies and cause splash dmg. Next you can spam a bunch of low AP Twisters and regen some AP while using magic missile (seeker). This will also build up flash of insight and once you have 5 unleash Arcane Torrent an extra 75% damage on a group and watch them explode.
While this build is not particularly survivable on its own I found it works great as support and especially in close quarters like much of Act II and III due to the fact that tornadoes bounce around hitting multiple enemies.
Tweak and enjoy.