Diablo® III

So everybody can go tl;dr.

Hardcore Monk (first character): http://eu.battle.net/d3/en/calculator/monk#UWXdeQ!cbT!cZbbZZ

Spirit Generators:

• Way of the Hundred Fists (Windforce Flurry Rune): This is the damage dealing Spirit Generator. It seems it will be the most potent damage-wise, and since the rest of my build doesn't use a lot of Spirit and/or has passive Spirit generation, Fists of Thunder isn't obligatory for decent Spirit generation.
• Crippling Wave (Concussion Rune): The Spirit Generator for situations where the incoming damage will be greater (typically elites and superior). The interesting thing about Monks is that you can use combos with different Spirit Generators, a good combo for intermediate incoming damage might be Way of the Hundred Fists x 2 + Crippling Wave for the third, debuffing hit.

Techniques:

• Breath of Heaven (Blazing Wrath—Tentative Rune): I think it's a very much needed ability in Hardcore and I won't be surprised if it becomes a staple of HC Monks builds. The rune is used to provide a nice buff in case you need the heal, to maintain a good DPS level. If the heal is deemed too feeble I'll replace it with the Circle of Life one. Other runes are pretty underwhelming in their effects.
• Dashing Strike (Quicksilver Rune): This ability adds so much ability it's ridiculous. Very good for escapes, the Quicksilver Rune makes it spammable with little regard to Spirit.
• Wave of Light (Explosive Light Rune): AoE ability. Very potent, a bit tricky to use position-wise, Explosive Light makes it more useful in bunched packs.

Mantra:

• Mantra of Healing (Circular Breathing): The main point of the Mantra is Spirit Generation to free the use of Wave of Light, though the healing is a most welcome perk in a Hardcore environment. The on-use buff might make a potent additional healing ability if things went south.

Passives:

• Chant of Resonance: Took that for the Spirit generation mostly. Less upkeep is still nice to have, freeing some Spirit usage for Wave of Light.
• Exalted Soul: Enables multiple usage of Wave of Light for bursting purposes while still having enough Spirit to use Breath of Heaven.
• Near Death Experience: Well, it's a Hardcore character after all.

The main Spirit Generator would be Way of the Hundred Fists, the main spender would be Wave of Light, plus various utility spells (healing, mobility). A rather rounded spec, which I will tweak I suppose if I have to battle elites+ with tricky combinations.

Build for Softcore for all around offensive/defensive power. Suppose would work for PvP also with some modifications.

http://eu.battle.net/d3/en/calculator/monk#aUdgTk!gUT!Zcbaaa

Spirit Generators

• Fists of Thunder - Lightning Flash OR Crippling Wave - Breaking Wave
  Almost constant dodge bonus for free or if you want more damage go with Breaking Wave
• Way of the Hundred Fists - Windforce Flurry
  250% Weapon Damage at the 3rd hit? Must have, as no other combo seems to come close in damage.

Techniques

• Dashing Strike - Quicksilver
  For movement with reduced spirit cost
• Breath of Heaven - Blazing Wrath OR Serenity - Peaceful Repost
  Damage and healing or if you want invulnerability and healing go with Serenity.
• Seven-Sided Strike - Sudden Assault
  The big hitter. Runed for maxium damage.

Mantra

• Mantra of Conviction - Overawe
  Moar damage. Also works as Spirit dumb for double effect which should also work well in conjunction with SSS.

Passives

• Combination strike
  If it works as I suppose it is pretty much constant 16% extra damage which makes it must have along with WHF and Overawe.
• One With Everything
  It just is ridiciously good defensive skill if resists are even remotely as important as in DII
• Near Death Experience
  Another borderline overpowered ability? Yeah I mentioned I like them.

Pretty Spirit light build. Should do high damage just by spamming WHF 3rd hit with capacity to very high burst damage Activating Mantra and hitting SSS. Also comes with Defensive utility. Very customizable because of low Spirit need.

Your combo should go most of the time Crippling -> WHF -> WHF
First hit 110% weapon damage debuffing enemy for +10% damage taken and giving you 8% damage buff from Combination strike, second hit 140% weapon damage increasing your damage buff to 16%, third hit launching the 250% weapon damage WHF blast with 16% damage buff and +10% damage taken debuff on target.

I've managed to theory-craft a pure PvP build. Problem is, I don't know if it'll work as intended due to nill practical knowledge of higher level skills and runes.

Glass Shatterer - http://eu.battle.net/d3/en/calculator/monk#aWdiTS!Zed!ZYcZaa

Spirit Generators

• Fists of Thunder (Lightning Flash) - Explained below
• Crippling Wave (Tsunami) - Skill for attack speed reduction, rune for the larger AoE movement speed reduction, hoping to periodically cripple the opposing team

Techniques

• Dashing Strike (Blinding Speed) - Rushing to enemies if SSS is in cooldown, dodge explained below
• Sweeping Wind (Blade Storm) - Explained below
• Seven-Sided Strike (Sudden Assault) - Main damage dealer

Mantra

• Mantra of Retribution (Retaliation) - I'm taking retribution because no matter what, your team will get damaged at all times in the arena. This skill makes sure it's NOT free damage. Retaliation for extra pain and making it work against ranged as well.

Passives

• Resolve - Explained Below
• Pacifism - Makes status effects' usage almost undesirable against my character, allowing free movement in the arena
• The Guardian's Path - Want to dual-wield for extra magical affixes, dodge explained below

General gameplan
So the basic idea of this build is to have as much dodge as possible to irritate attackers (possibly making them attack others first - here's where mantra comes to effect) and to be a thorn in the enemy team's side while aiding my team as much as possible. The goal for this build is to pick off wizards, demon hunters and witch doctors (mantra's Retaliation rune reflects their attacks). SSS/Dashing Strike closes the distance, while Sweeping Wind with Blade Storm rune adds some extra damage for obliterating them. Since my enemies are glass cannons, Resolve helps manage the incoming damage.

Possible Downsides
As I said at the beginning, I have no idea how dodge accumulates with some of these skills, so I'll have to test that. Also need to check for exceptions for Mantra of Retribution. Lastly, I have no idea if I can generate/keep enough spirit for seamless execution of this build.