I am saving a particular black soul gem to create a special weapon.
It's the soul from the person you kill for the big DB quest
It might be called -
Any weapon - The PersonTitle's Revenge, Wrath,
Sword or Dagger - The PersonTitle's Edge or
Helm, Cowl, Circlet - The PersonTitle's Crown, Skull, Mask
or maybe Soul, Spirit or something like that
where PersonTitle's is the characters title (to not spoil anything
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)
Also created a couple bows
Soul Stealer - Soul Trap
Storm Shadow's Bolt - lightning (i know i'm a GI Joe Dork)