D4:Old School Prestige Classes
This could meld well with Zak’s location based feats idea as well. Also, notice the blog itself is now part of the blogroll.
If I ever run True20 this might be what I use for advancement instead of the system Chronicles of Ramlar, despite the principle reason I own the later is its experience system.
I like this quick and dirty way of determining spells for new characters. It would mesh nicely with the idea of having specialist magic-users from 2nd/3rd edition (easily portable to OD&D) be based on a tradition instead of a college. What if Hurgh’s spells are forever banned to students of Rhialto due to incompatible theories of magic?