An Abominable Fancy: Boring Spells: a completely flavor-drained spell list, just straight mechanics. Want a Fire Mage or Shadow Walker or Time Lord or Gadgeteer or whatever? Just pick the mechanics you need and dress them up in lovely fluff. Also, some examples.
DMiurgy: Standard Spell List as Fighter Techniques: Allow fighters to learn spells but give them different names. Charm Person turns into Oath of Merciful Indenture – “You can hold someone at swordpoint/arrowpoint/gunpoint etc and demand they surrender and serve you, or perish!”