My favorite part of the book is how all the weapons and martial arts systems do ridiculous and inflated amounts of damage just because they're asian. A shuriken can do 1d6 damage...that's the same as a "short sword" from the Euro-centric Rules Cyclopedia. There are ninja eggshell grenades that are ridiculously overpowered because without using magic, or requiring a high character level, they ignore armor on the attack roll and can incapacitate anyone who fails a saving throw for 1d6 rounds. So as I understand it, that means a level 1 ninja who succeeds in hitting his level 10 opponent with a pepper-filled eggshell could incapacitate the opponent who is "choking and sneezing" for up to 6 rounds, which in turn means that anyone who can get a melee attack in on the incapacitated opponent can instantly kill that character as if affected by Stinking Cloud. There are also flash powder grenades that, when thrown into a fire, automatically blind everyone who was looking in the fire, no saving throw, for 1-3 rounds. Only if you "may or may not be looking at the light" are allowed a saving throw. So probably one of the top rules for surviving an Oriental Adventures campaign is to tell the GM your character never looks at a fire.
There is a huge amount of material concerning honor, family honor and personal honor. To make a long story short it's hard to gain honor and easy to lose it, but at the same time if your honor drops below your family honor levels, you actually lose certain character classes. You can't be a kensai, for example, and if your honor drops below that critical point, you revert to a bushi and your character advancement tables and ability advancement is forever changed. Also depending on dice rolls for family background your character can possibly inherit valuable property. What's most interesting about this is the assumption on the part of the authors that that would be an oriental, and not European phenomenon. In my opinion, medieval European societies would have been comparably preoccupied with family honor and personal reputation. I think that any time you have a pre-industrial society without telecommunications of some kind, local family support structures and local reputation are going to be of paramount importance. How else would someone know if you're trustworthy to work with or not? If you travel the world today and get away from post-industrialized society and culture you'll see a similar emphasis on family, and a de-emphasis on the self as a totally autonomous unit. It was really the industrial revolution and the advent of the modern wage or salary that allowed people to disassociate themselves from their families. So, in conclusion, I actually like the emphasis on honor in Oriental Adventures, but feel it's incorrect to imply that stuff existed in Asia but not in dark ages medieval Europe.
My most favorite part, of course, is martial arts. If you have proficiency in karate, you can get 3/1 attacks per round, an AC of 8, and 1d6 damage per punch. You can also gain an "iron fist" special move that allows your damage to be 1d10 per punch, just like a goddamned two handed sword. You can take Crushing Blow, which lets you break 1/4" of stone per level, or normal damage plus your level to a living target. Finally there's also Eagle Claw, which lets you, once per round, do 3d10 damage and "shatter objects (snap spear shafts, crush stones, etc.)". So basically you can go around destroying everyones' weapons and make them unable to attack you effectively unless they also have a martial art style or magic or something. A regular D&D fighter could be totally screwed by some karate dude Eagle Clawing his sword.
The stuff in Oriental Adventures is so extreme and hilarious that if I had the time, I'd seriously try to organize a game. After the player characters had gotten their feet wet they could all travel to Mystara where they humiliate all the honorless proto-Europeans by eagle clawing their +3 flaming swords and making them cry when the sword breaks.
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EDIT: Your character could totally be named Segata Sanshiro.
EDIT 2: http://www.youtube.com/watch?v=uUjIA3Rt7gk