Improved Grapple [General] [Fighter]
You are trained in the art of grappling.
Benefit: You do not provoke an attack of opportunity when attempting to grapple an opponent. Your grappling checks are at a +2.
Normal: See the normal grapple rules, PHB page 137.
Crushing Grip [General] [Fighter]
The iron grip of a wrestler crushes bones and inflicts terrible injury on foes. A wrestler may subtract from his grapple check (by up to his base attack) and add this number to his damage inflicted, this effects all grapple checks that round and is identical to the Power attack feat, but can only be used while maintaining a grapple.
Power Throw [General] [Fighter]
Prerequisite: Improved Grapple, BAB 3+
After pinning an opponent, a student of grappling can lift them over his head (providing they weigh less than the 'lift over head' weight on page 141 of PHB) and hurl them away from him with great force.
If the grappler succeeds in a grapple check against a pinned foe, he can throw the opponent a distance of 5' + 1' per point he beat his opponents roll by, causing normal unarmed damage (plus STR bonus) and knocking them prone. A successful Tumble check (DC 10+distance thrown) can allow for rolling out of the prone position as a free action, and critical success reduces throw damage by ½.
For each size category the grappler is larger than his opponent, there's an extra 5' of distance and an extra damage increment (1d6 becomes 1d8, etc).
This move breaks the grapple regardless of whether it works or not.
Alternatively, this feat can be used against charging opponents if you have initiative, or are delaying (setting yourself to receive the charge) to use the opponent's efforts, movement, and momentum to aid in the power of your own throw. This can be used to throw a charging or bull rushing opponent 10ft. while inflicting double damage. The use of this throw requires two hands if not the entire body to execute. This technique can be used only once per round.
Immovability [General] [Fighter]
Immovability enables a person to control his body weight and use leverage as if he were exceptionally stable. He gains a +4 stability bonus to resist any attempts to upend him, including grapples, throws, trips, and bull rushes. It can be used when flat-footed.
Earth's Embrace (modified from Oriental Adventures) [General] [Fighter]
Prequisite: Improved Grapple, STR 15+
If you pin an opponent while grappling, each round you maintain the pin you deal critical (double normal) damage. You must stay immobile, giving other opponents +4 to hit you.
In lieu of this damage, you can instead deal 1d4 points of temporary Str or Dex damage, by applying great pressure to limbs and joints.
Finishing Maneuver
Once a wrestler has grappled AND then pinned his opponent, he may demonstrate his utter dominance in hand-to-hand combat by launching himself and his opponent into the air, then back to the earth, dropping the opponent head first with the weight of both bodies in a powerful attack. The opponent suffers normal damage but the damage bonus for Str is doubled. The opponent is now considered prone and must also make a fortitude save (DC10 + character level + Str bonus) or he becomes stunned for one round. This maneuver is usable up to (3+CON bonus)/day.
Extension to normal grappling rules (available to any character in a grapple):
Takedown: by dropping his body to the ground the Grappler takes his opponents down with him and makes them prone. On a successful trip check made during a grapple (no follow-up attack as Improved Trip normally allows), the Grappler and his opponent both fall to the ground, the opponent then becomes prone, whereas the grappler is not (but only to the opponent he has grappled, to other opponents he is considered to be prone), giving him +4 to his grapple checks as long as he continues to win the checks. A failed takedown (trip roll) results in the grapple being broken.
Many of these feats could be combined into a Grappling/Wrestler prestige class which would help a character to become quite proficient at this cool alternative combat maneuver.
I've modified The Mighty Contender of Kord prestige class to include these feats.
