I particularly like my minor artifact of spell preparation, although it is basically fluff for your divine metamagic persistent buff machine. You lock in whatever spells and abilities you cast everyday as part of your buffing routine. Unless you change them, the item just automatically takes those slots and abilities and puts up the buffs. It also acts as a bag of holding for items that affect your spells, counts as a ring of sustance, and has the Dragonlance spell effect that you don't ever need to sleep even to prepare your spells (cannot prepare any slots you used in the last 8 hours though). It also removed the required time to prepare/pray/etc to get your abilities each day. It covered all mundane/ no gp spell components, stored focuses, and held any additional spell components of value. It was summonable from any distance/plane.
So basically if you wanted a Divine power spell put up every two days with divine metamagic persistent, extended, bead of karma, and the dweomerkeepers supernatural spell it just did it for you taking up all your necessary abilities. Or alternatively at high levels you could lock in 3 copies of a 10 min per level duration spell to pick up 24 hour coverage without having to worry about at what points in the day you would have to recast it. Also anything like metamagic rods, beads of karma, ahnk of ascesion, etc. were put in the item and just worked.
The main reason for the item was I was playing a warforged and I thought it was extremely lame that a warforged that did not have to sleep but had to sit around 8 hours a day just to prepare his arcane spells. Also the ring of sustance is lame for spellcasters because instead of sleeping 8 hours to prepare spells, they sleep 2 and stare at a wall for 6 to prepare spells. Overall the item was mechanically transparent, but convenent for the character. Works well epically with the artificer paragon path that makes your equipment immune to Disjunction and you casting supernatural spells.
