Can an activator be activated by a spell? In Oblivion there was a pillar that you had to throw a spell at to cause something to happen,

Yes it's possible, I've seen Il Ducey do some interesting things with this. Doesn't mean I actually know how he did it though (I'm pretty sure he wrote a tutorial on the subject in here somewhere...)

Try adding an ObjectReference script to an activator with an OnHit() event

- Hypno