Needs review
Source: Epic Level Handbook

Description: You can prepare spells that exceed the normal limits of spellcasting.

Prerequisites: Epic Level, Ability to cast spells of the normal maximum spell level in at least one spellcasting class

When you select this feat, you gain one spell slot per day of any level up to one level higher than the highest-level spell you can already cast in a particular class. For example, if you select this feat as a 21st-level wizard, you would gain one wizard spell slot of any spell level up to 10th. You must still have the requisite ability score (10 + spell level) in order to cast any spell stored in this slot. If you have a high enough ability modifier to gain one or more bonus spells for this spell level, you also gain the bonus spells for this spell level. You must use the spell slot as a member of the class in which you can already cast spells of the normal maximum spell level. For instance, a 5th-level ranger/22nd level sorcerer couldn't add a ranger spell slot, because he can't cast spells of the normal maximum spell level for ranger. He must add the spell slot to his sorcerer spells.

Special

You can gain this feat multiple times.