There are two things I quite like. Multiversal nexusses and communal projects. So I thought I'd put them together and see what happened.
So the game is set on an infinite world in which all realities sort of blend together to form a semi-cohesive reality all of their own. The intention is for setting to be both pliable, expandable, and, yeah, a little bit mismatched, for lack of a more severe word. If my plan pans out (which, should history be any guide, it has about a one in ten chance of doing) there should be one core rulebook, written by largely by me, and lots of setting books written by all of you guys adding character choices, items, monsters, locations, NPCs, and adventures.
Obviously, you can't really do that without some idea of the mechanics, but since I'm such a newbie I want you to weigh in before I set anything down in concrete. But here's what I have so far;
Everything is based on rolling one type of die, I'm thinking a d4. Rather than concrete attributes and ability scores, it seems natural that this would use a wide, pliable range of skills, and each rank in a skill would equate to 1d4 that you role for applicable skill checks. Characters are defined by one Race, three Niches, and their Individuality. Usually, Race will give general skills like Brute Strength, as well as specific racial bonuses like Night Vision. Niches are like classes, and would give you more specific skills, like Axemanship. Individuality provides skills that make the character special, and would be provided by the player and approved by the GM. When a thing needs doing, a player puts forth what they're doing, then applies whichever of their skills they can talk into being relevant to it. Either the GM will set a DC for the check, or will roll for a character to oppose the action, using their own skills.
So, that's what I got going. If you guys think that sounds fine, then feel free to start contributing immediately, because frankly I'm interested in seeing what, when given limitless options, you choose to create.