Just a note. I haven't read through the entire 7 pages so if this was already mentioned don't mind me.
Spontaneous Divination (5th ACF for Wizards) allows Wizards to legally take the Versitile Spellcaster feat (RotD).
Being able to sac two lower level spell slots to cast a higher level one from your spells known? Lets look at this from a wizards perspective.
Your spell slots are your memorized spells per day. Now I dont think this allows you to sacrifice memorized spells, but unused spell slots are definate candidates for Versitile Spellcaster.
A wizards "spells known" are effectively any spell he has scribed into his spellbook.
So this seems to open up three very interesting tactics. First, we can leave two slots unmemorized for the day and sacrifice them to instantly
cast any spell from our spellbook of 1 level higher. Key words "
cast any spell from our spellbook" Versitile Spellcaster indeed.
Secondly, if you can afford to scribe a spell into your spellbook 1 level higher than you can currently cast, this trick allows you to legitamately cast 1 spell level higher than normal. This is because the spell scribed in your spellbook is effectively added to your list of spells known. Not 100% sure on the legitimacy of this but it could prove interesting for getting into certain PrC's earlier than normal? Wizard 6/Shadowcraft Mage without Earth Spell/Sanctum spell hijinks?
Lastly there is the possibility of applying metamagic feats to the spells you spontaneously cast. This one I honestly have no idea if it is feasable or not, but it seems like it could very well be possible. Although having to leave 4 unmemorized slots for the day just to cast 1 metamagicked spell seems a waste.
Can anybody verify my ideas? Or has someone already pointed this out? Please I must know.