Ok, I have a serious question now...
The "sacred geometry" feat listed earlier could be employed to tremendous effect, if paired with item creation, since metamagic effects can be imbued into magical items. If used exclusively with item creation, (and taken several times), a very successful player character (has lots of money to burn) could create some pretty absurd magical items that technically only consume a low level spell slot. (eg, create wands with stacked metamagic effects without exceeding the wand's low level slot reqs.)
Since the magic of a magic item is very different than the one-off casting of a spellcaster, once the necessary rolls are successful in item creation, the resulting item would be able to routinely cast the spell for them in that manner. Say for instance, a staff (or wand). This means that the dice roll fudgery of the sacred geometry feat need only be completed at item creation; the spell is then stored inside the staff, and gets the 10 charges. The creator is technically "able" to cast the spell that way, and thus can charge it every day, and has a boom-stick to fire it off with quickly.
Taking that feat, and combining it with item creation in this fashion could result in some very interesting (and likely VERY OP) consequences. (say, a wand of magic missile that is heightened, empowered, enlarged, etc... all at the base cost of magic missile, since the spell level is not raised by the additional effects. Wands get 50 charges off the bat, so constant attempts (and failures) to create wands with this feat would result in deadly sticks of doom that mostly negate the difficulty of using the feat, due to the number of charges granted on successful creation, as the number of charges granted in a wand mean you basically get 50 times the economy. The feat says "one, both, or all of the feats already gained" which means if you take this feat several times, each time taking 2 more metamagic feats, wands that shoot pure horror become a very real thing.)
Or, am I reading this incorrectly?
Another that could possibly be combined with this feat is Inscribe Magical Tattoo, which would allow the caster to "wear" several buff conveying "wondrous items" without interfering with actual magic item slot use. Metamagic enhanced versions could make use of the sacred geometry feat without increasing the spell level.
Surely there is something to prevent abuse of this type, right?