Okay, so here's where I explain how this all works.
I've been bouncing d20's for about twenty years now. A lot of that has been on the side of the screen where all the charts and tables are printed. I love playing too, but D/GMing and world building is a lot of fun for me.
The campaign I'm running is what has become known as a "Sandbox" campaign. (The inspiration for this comes from the West Marches campaign, but there's plenty other examples of this style of play knocking about the gaming blogosphere.) What that means, for those who don't know, is that instead of devising a story for the characters to follow, I am stocking a setting with a variety of perils and prizes and allowing the characters to explore as they wish.
Because of the flexibility of this milieu, I'm also experimenting with the logistics. Instead of the usual 4-6 players that most contemporary RPG's seem to support. (3rd Edition D&D, which is the system I'm running it in, seems to base all it's calculations on four players, for example.) I've recruited a wide pool of potential players from the extensive Boston gamer scene that I find myself fortunate to be a part of. Every Saturday night, I run a session, with a sign up sheet for 4-8 players from the pool. Right now I've got about 16 recruits, which is a pretty good number.
The one requirement of play is that the adventure must begin and end at the home base, so that a different mix of characters can form up at the next session. To enforce this, I've taken inspiration from Jeff Rients' "Triple Secret Random Dungeon Fate Chart of Very Probable Doom" and instituted what I call the Calamity Tables, wherein if you are in the field at the end of the session you must roll a check to get back home or you suffer a woeful calamity (The mildest of which is you stagger back into town with nothing but a single hit point, a case of amnesia, and a persistent facial tic.)
So anyway, that's the structure of this endeavor. As the weeks roll by I'll be figuring out what of this works and what doesn't.