Here's the basics on the SovStone magic system, cut and pasted from a recent chatroom conv i had about it.
there are no spell levels or spells per day limits
instead, spells have whats called a Casting Threshhold
wizards generate 1d20+casting bonus points per round to apply to the CT of a spell
when you reach the CT, you cast the spell
The more powerful the spell, the higher the CT.
each round of casting, you have to make a fort save (dc8to12, rises by one each round) or take 1d4 subdual damage, not to mention concentration checks if someone is beating on you.
so a 1st level wzard could theoretically cast a spell like wish, but realistically it wouldnt happen, the CT would be around 300 (or higher, possibly around 5 or 6 hundred)
most '1st level' type spells have a CT between 20 and 40, taking anywhere from 1 to 4 or 5 rounds to cast, depending on your roll and you casting bonus
they dont include CTs for the PHB spells, but they do have a fairly detailed method for calculating the CT for new spells though, so I've started working out the CT's for the PHB and R&R spells
they have thier own set of spells based around a 5 elements type scheme; earth, air, fire, water, void
when you cast void spells (stuff like necromancy) the damage is real damage, not subdual
That's not very detailed, but I think it gives the basic idea. It's really a great deviation from the standard d20 system, IMO.