I rather like the way magic works in Glen Cook's Black Company novels. Learning a mage's true name, and speaking it to them, strips them of their power, making their name the most guarded secret they have. They don't really have set spell lists...they build spells for the occasion on the spot rather than casting spell number 237B, and it can take centuries for a mage to get really, really powerful. Green Ronin did a D20 setting for the Black Company, and then later a splat for just the magic system called True Sorcery.