I suppose the thread title isn't exactly accurate to what i'm looking for.
There ARE plenty of bad-ass wizard games, but i suppose what i'm thinking of is a game where you can use your magic for a vast multitude of purposes, such as cooking, brainwashing, time control, diseases, etc..
Ech, maybe i have no idea what i'm thinking of in the first place D:
Well, Morrowind and Daggerfall do possess many "utility" spells, probably the most of any RPG. There's levitation, locking/unlocking spells, disease healing, skill buffs, etc..
I think any D&D based RPG (like Baldur's Gate, Neverwinter Nights or Temple of Elemental Evil) has wizards able to do similar things, like enlarging people, curing/afflicting disease, etc., but these come at the cost of deciding not to pick up an offensive spell instead upon leveling up (as that's how wizards gain spells). There's also other magic-related classes, but I'm not sure how they work or if they have similar capabilities.
Among roguelikes, I remember at least in ADOM that burning spells would result in enemies leaving behind cooked corpses which you could eat. And just about any roguelike will have you carrying around an assortment of wands and potions, allowing you to create walls/doors, teleport, polymorph, etc..
Also, I'm not sure if this is what you're looking for, but I recall magic working pretty physics-accurately in Dark Messiah of Might and Magic. That is, for example, you could freeze the ground, provoke an enemy into running over it and then watch them slip and fall (preferably off a cliff). There were also jugs of oil lying around everywhere, obviously meant for use with the fireball spell.
I also just remembered Slaves to Armok I. What other game gave you spells allowing you to teleport someone's brain out or turn their eyes to stone? Not really much use outside of combat, but there wasn't actually that much outside of combat upon its last release.