I've also been seeing quite a few great magic systems in development over the past few months. There was even a great discussion regarding the spirit sphere in Mage, and how the new game rules basically rendered it irrelevant except as a type of paradigm or focus to drive other effects in play (sorry, I can't remember who wrote this).
So, I'm thinking of returning to my "Storifying Mage" concepts, but now I'm considering a different angle.
My new thoughts are an assortment of keywords that get combined to produce mystical effects. 9 spheres, 9 lists of keywords in 5 levels. That's a minimum of 45 keywords, but we're probably looking at more like 90 (2 per level). Each keyword will have specific mechanical benefits and effects, magical power will determine the maximum number of words that may be combined for memorised effects (half this number, rounding up, to determine the words that might be combined on the fly for spontaneous magic effects).
I need to remember this stuff for once the FUBAR rewrite is complete, that'll be the next project.