UPDATE: 2/14/2013

This is just a list of a few of my house rules, some of which are to make the game more challenging and others to add more strategy options.

Threat Dice

Classify monsters as either Martial, Casters or Priest.

Martial Types

Gain one Threat Die for every three levels. Threat Dice are added to the creatures first melee or ranged attack damage rolls, similar to MDD this requires expenditure of a reaction on the part of the monster.

Caster Types

Do not gain Threat Dice.

Priest Types

Gain one threat dice per five levels.

Flanking

When flanked your attacks are at Disadvantage.

Attack of Oppurtunity

When Clerics or Wizards cast any spell which does not use Magic Attack to resolve while within a threatened square , they provoke an AOO

Ranged Attacks

When utilizing ranged weapons to attack an opponent within 10 feet, the attack is made at a disadvantage. If the opponent is not aware of your prescense
no Disadvantage is suffered.

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I will update this thread as time goes on

Note: If you have house rules you would like to add you are invited to do so.

PLEASE DO NOT MAKE REPLIES TO POST IN THIS THREAD,
THIS THREAD IS INTENDED FOR LISTING HOUSE RULES NOT FOR DISCUSSION OF HOUSE RULES. Thank You.*/

Cleric Re-write

Clerics gain 3 cantrips per day at first level, +1 cantrip every three levels.

Clerics gain 1 Word of Power at levels 3,6,9,12 and 15 at level 20 the Cleric gains "Divine Messenger" which permits unlimited use of Words of Power.

When a Cleric recieves a Martial Damage DIE, he or she may exchange each die he or she recieves in favor of a spell slot.
Any MDD exchanged in this way is lost.

General Class Re-Write

Fighter/Barbarian +1 per three levels

Rogue +1 attack per four levels.

Cleric +1 per four levels Magical Attack Bonus +1 per four levels

Wizard weapon attack +1 per five levels, magic attack +1 per three. 

Rising from Prone

When rising from a prone position uses full movement, a player may use a reaction to make a DEX save DC:14 (roll with disadvantage if flanked)

and reduce the amount of movement utilized by half.

UPDATE: 2/12/2013

Click the Dice.

House Rules: I use these in the current series I am running. Its heavily magic laden.

1. Every Player was required to roll on a series of random tables to determine key aspects of thier backgrounds. Such as Family members, rite of passage, past crimes, quirks, hobbies...ect. All information was used RP only to flesh out each character to better place them in a custom campaign setting.

2. Magic has been changed to an Arcane Dice System. Magic Users gain Arcane Dice which is used to cast spells. Similar to Martial Dice in usage however Arcane Dice only refresh 1 die per round in which the Magic user made no attacks or took no damage. Spells cost 1 die per level. Spell feats are used by expending Arcane Dice as well. Dice progression is as Follows.

Magic User             Arcane 
Level                      Dice
1 -                          2

3 -                          3 

5 -                          4 

7 -                          5
 
9 -                          6

11-                         7

13 -                        8

15 -                        9

17 -                        10 

Magic Users still have to prepare spells at 1 + Level. Some spells have been moved over to Ritual Only. Spell components are in full use. (Work in Progress)

3. Weapon Proficiency - Players start with specified class weapon proficiencies. Using a known weapon incurs no penalty and standard damage. Being Unproficient yields a -2 penalty to hit and reduces the Damage of the weapon by 1 die type accordingly. D4 to D2, D6 to D4...ect. Fighters can specialize in a weapon. By specializing the fighter gains a +1 bonus to hit with the weapon and the Damage die for the weapon increase by 1 die type. Racial Bonus does not stack with Specialization.  Further Mastery of a weapon is possible with continual increases. This option has been explored in game yet however.

4. Fate Points - Players are awarded a Fate Point when the DM invokes a an unwinnable situation in order to advance the adventure. For example Bad escapes at the end or players are restricted from making a save in an approriate situation. Players may spend a fate point in order to alter the game to their favor. For example force a Reroll on a die. Score an automatic pass on a skill check, rewind the clock and prevent an untimely demise. I add these in to allot of my games as it gives the players insurance. While some RP heavy groups are fine with the DM "breaking" the rules for NPCs, others seem to have a sore spot for it. By adding Fate Points and using a DM "Fiat" it calms the timid and makes them feel more secure. In the event that a Fate Point is used to override a Fiat a Veto may be called. If a Veto is called the player who spent the intial Fate point has it returned and another Fate rewarded.

Thats all I can think of for now. So far its been pretty smooth. The Arcane Dice allow the Mage to cast more often, but with the median time for encounters being a couple of rounds he generally is being out performed in Damage by the Warrior.