First off, the production value in this book is fantastic. All of the art work is top level stuff and the writing is consistently good. Some of my favorites, both for flavor and for crunch:
Ki Balance: Dodge with a cherry on top. It gives a +1 dodge bonus, but also allows you to spend a ki point to avoid being tripped or knocked prone. Handy!
Ki Insight: +2 Sense Motive and use a ki point to boost a will save or opposed check. Good synergy with the Snake Style feat if you are going unarmed.
Align Ki: A great way to give your weapon an impromptu Axiomatic / Anarchic / Holy / Unholy kick!
Kiai Feat tree: Fantastic flavor. A tree of shouts that can deafen, stagger, push foes back, deal damage or boost specific rolls. I want this just so my ninja can run around shouting "Fus Ro Dah!
All in all, a good way to improve the options for your Ninja. And if you have forgotten trick it opens a door to some very interesting possibilities.
