Okay, so the problem is that I do some of my best and worst thinking (mainly RPG/game ideas) late at night. It becomes a sort of manic-depressive swinging creative method: lots of highs, lots of lows, little rationalization. This basically means there are plenty of interesting ideas, with no realization of the obvious gaping flaws in implementation.
The latest was an idea where players were characters in someone's dream, but had to do battle (within the framework) to find out who would "survive". I'd come up with a decent card mechanic for this, but something just didn't feel right. Looking at it again, I just found that the idea, well... fucking sucked. By the light of day it was cobbled and weak, and it didn't even sound right rolling off the tongue. It was too open-ended, and couldn't reasonably be saved from the spiraling tug-of-war that would result from such an open-ended plot concept in a GM-less system.
However, just looking at what was running through my head during the creation, and the type of play I envisioned, I think that with just a bit of a premise shift, this can become awesome once again.
So... similar mechanic, new setting, new premise. Let's rock: Collabarative/competitive horror storytelling.
Pre-game, players should have agreed on a general setting for a horror-based story. This can be achieved any number of ways: round-robin per-story, general consensus, whatever. That's unimportant. The setting should be as general as possible: only enough to support a backdrop and to merely "set" the scene. Story should not be predetermined. Good: "1987, cabin in the woods." Bad: "A sleepy little town with a killer on the loose."
Players have two roles: First, they own characters in the game, whom they seek to keep alive, sane, and unharmed. Second: They are narrators, seeking both to create a compelling story, and to take down their competitors. The game has no permanent GM, although someone may take a "banker" role, guiding play order and other purely mechanical matters.
Players have a hand of (#?) cards available, that may be story elements: "Furniture", "Creature", "Person", "Fact", "Situation", "Scene", "Story". (More powerful cards are less available.) Players can lay a card, and describe a scene around the elements now in the story. (Cut slips or markers should be made to annotate the cards with what they represent.) Players must also "power up" their card by way of "Ching Points", described later.
Given these sometimes conflicting roles, and the power of the sitting storyteller, this might look to end up as a chaotic mess. That's where the Ching Points* come into play.
Things should be as fucking awesome as possible. This is key to many things in life, and this game is no exception. The mechanic keeps things Fucking Awesome by way of group feedback to determine sitting-storyteller effectiveness.
While cards are played to determine what is happening, the relative importance, strength, and longevity of the elements in scene are determined by Ching Points. Every player starts with a number of Ching Points equal to the number of players in the game, and each player gets one Ching Point per round. Ching points are best represented by pennies or small tokens. Each player also has a voting token.
Each player should have two bowls, cups, shot glasses, or the like in front of them. One is their Positive bin, and one is their negative bin. If other players find the player's move or description to be Fucking Awesome, they can put one of their Ching Points into the player's positive bin. If another player finds the move to be Supremely Lame, they can put a token in the negative bin. The player can keep and use any Ching Points in their positive bin, but must discard any in their negative bin, as well as an equal number from their positive or reserves.
Chings can be given at any time during a player's narration, so they can even bank on something being so Fucking Awesome that others will pitch in Chings to make it happen. Likewise, players going down a Lame path will find their Chings drying up into negatives, and having to dig into their reserves or give up their Lame storyline. This is commonly known as Calling "Bullshit". In extreme cases, fellow players may be forced to Lay Down a Karmic Ching Bitchslap on someone sinking far too many of their own points into something Lame.
Table talk, threats, promises, are all encouraged.
Ching points are used to give weight to a player's cards, to overtake past story elements or to protect them from being overtaken. Ching Point tokens are laid on top of cards, and that becomes the Weight of that card. If a player wishes to remove or augment a story element, or to control it themselves, they must do two things: First, devise a story with any associated cards needed to achieve the effect Fucking Awesomely. Second, pay (discard) enough Chings to drain out the other player's associated cards.
If you merely want narrative control of an object, you must buy it out, and have the same type of card to replace it with. This alone, without story, can cause a Silent Transfer of any story element that is not immediately intertwined with other objects. (An NPC, a piece of furniture, or a knife that's just lying out unbrandished.) For something that is held or used integrally by other story elements, you must have story and supporting cards to take control, or Silent Transfer everything. The Silent Transfer for defensive purposes should be considered Lame, but if it's to add suspense to some sort of master plan, that's Fucking Awesome.
Character sheets are kept simple. Characters have a list of Attributes, expressed as simple sentences: "Drop-dead gorgeous", "Good at Math", etc.. These have no set mechanical value, but can be called into play as a defensive measure to influence player Chinging.
Sheets also have a non-specific set of "wellness" indicators. These are detrimental things such as health, sanity, mutation, and the like, and new wellnesses are simply called into play whenever needed. When the points on a given stat are maxed, the player is incapacitated and unplayable.
Mechanical damage is done by way of a vote, or, more specifically, a vote when needed. At the end of the player's narration, or in the case of a major event (piano falling on someone mid-scene), after the target has had time to defend themselves, the player will simply state something like "...and Bob takes 3 points of sanity damage". If this is deemed reasonable, it is so. If it is deemed unreasonable, other players may work to compromise. If no compromise can be quickly met, a simple show-of-hands vote determines whether the stated effect takes hold. The vote is all-or-nothing.
...
Dammit, I have to go to sleep now. More later.
* "Ching Points" name shamelessly stolen from Everything2. Think "sound a cash register makes".