My Mage was always to busy spamming Lightning so I tried it:
I thought: Hey, Weapons dont lose charges when followers use em. Maybe also Soultheft works?
I made an enchanted advanced nordic 2h-axe with Soultheft and gave it to Lydia.
So i gave her a few dozen different Soulgems and let her steal all the enemies Souls.
Every few trips I exchange her filled Soulgems with empty ones.
Pretty usefull if you dont have to take care of this

Next Time I will give my nordic buddy who tanks for me some dual-swords with lifeleech and frost-restist-armor, summon some frost atronarchs so i can use my mighty frost-aoe without aggroeing and killing them

I need to do this for my dual enchanted daggers.