Ugh, I have a lot of them.
Destruction: Everything except for Sparks, Fire- and Lightning Bolts. Just never really got around to using them and for some reason they seem a bit boring to me.
Illusion: Clairvoyance. Does anybody actually use it? Really, it's kinda useless.
Restoration: Turn Undead. Never even tried it. Seems kinda... meh.
Alteration: Ash Rune & Shell and Paralysis. I usually just stop at Apprentice for the resistance perks, and I can live with Stoneflesh (I think?) just fine.
Conjuration: Zombies & atronachs. Never been much of a summoner. The Dawnguard summons are pretty cool though - and I love bound weapons.
I prefer using the spell Fear and spending those worthwhile perks to get Master of the Mind. With all appropriate perks, fear has a stronger range of level effectiveness and is boosted even more if your character is a Vampire and hunting the undead. On top of that, I welcome the boost to fire spells through Aspect of Terror, since it acts like a Level 99 Fear effect.
I know I'm a little late to this but that's not gonna stop me
My second build used low level turn undead spells to stagger deathlords and other stronger undead to give it a chance to attack without having to worry about the deathlord countering. Which was helpful considering it's low AR and health
It really is! Frosty is the best follower for a level 1 character. There when you need him, unsummoned when you just want to wander around inside the inns and narrow hallways.
And I'm really enjoying the fun of necromancy in my Sorceress playthrough. Watching cave bears and saber cats tear into bandits...
Destruction: Whirlwind Cloak and Lightning Storm. I like them both but I've never used them in any meaningful way.
Restoration: The AOE healing effect, forget what it's called. I always stick to the targeted effects, don't want to accidentally heal my enemies. And I never use wards, except when Tolfdir makes me.
Illusion: Clairvoyance, seriously why is this even in the game?
Conjuration: Love them all except Dremora Lord and Bound Battle Ax.
Alteration: Dragon Skin and Telekinesis (except for instantly leveling to 100 Alt)