Doing more than damage on an AoO?

[deuxhero]

What are the ways to accomplish this aside from combat maneuvers, magic weapon properties and spells that improve weapons?

The ones I know of are Enforcer/Cornugon Smash (possibly, PF waffles on free actions out of turn), Dazing/Stunning Assault, Aberrant Bloodrager's Staggering Strike and the various critical feats.

[Lerondiel]

Deft Opportunist & Power Attacking for 4?

[deuxhero]

1: That's 3.5
2: That only gives a bonus to attack roll, not an additional effect which is what I'm looking for.

[CGNefarious]

If you're down for Dreamscarred Press material, Seize the Opportunity would do what you're looking for.

[deuxhero]

I was actually looking for the sake of making an interesting melee character without having to use DSP stuff.

[Lerondiel]

1: That's 3.5
2: That only gives a bonus to attack roll, not an additional effect which is what I'm looking for.

No probs, I was tired and read the thread as "Doing more damage on an AoO lol

[avr]

Bloodragers can use a ring of blood vengeance to cast a spell as an AoO. Subject to caveats regarding off-turn free actions, anyone with a spell storing or dispelling weapon could do the same. - edit - read the OP again.

The bodyguard feat turns AoO's into aid another actions for AC.

[SangoProduction]

Isn't there a feat that makes it so that, instead of attacking, you stop them from moving?

[Necromancy]

Isn't there a feat that makes it so that, instead of attacking, you stop them from moving?

Stand Still

[grarrrg]

(possibly, PF waffles on free actions out of turn)

The FAQ (http://paizo.com/paizo/faq/v5748nruor1fm#v5748eaic9shq) would imply that most anything that is/triggers on (successful) attack allows an Off-Turn Free Action.
So I don't see why Enforcer/Cornugon should be all that different.

[Drelua]

Well, there's the Two-Weapon Warrior Fighter archetype which gets a few abilities that have to do with AoOs; letting you attack with both weapons on an AoO, letting you add a trip, disarm, or sunder to an AoO as an immediate action, and making it provoke to attack you. Unfortunately, those last two abilities come at level 17 and 19, and the archetype's pretty bad over all. For one thing, it's weapon training equivalent only applies when making a full attack, not a standard or an AoO, and for another, you still need the DEX for the TWF feats, but you lose armour training, so your AC won't be as good as it could be.

I'm only bringing up this archetype because some people seem to have a much higher opinion of it than I do, but if I was going to make a TWF Fighter, I'd just go with Mobile Warrior. Their ability to move and full attack is a lot of fun, though I've found it to be more effective with Lunge and a reach weapon. Then again, trading your first attack for a move action is a smaller cost for a TWFer, so that's worth considering.