Okay, I know, I probably shouldn't be starting a new thread for this, but this is just such a great idea for a game that I can't keep it pent up inside me.
Okay, here's the idea: The game is set in the very near future, say, 2008 or 2009. In Carver City, a city similar to New York and other major cities, a series of massive, devastating earthquakes cause thousands to go missing or dead. Within a day, heavy rain causes the weakened coastal areas to begin sinking, causing floods and occasional landslides. And, even worse, strange, lanky, humanoid creatures resembling popular depictions of "mole people" begin emerging from the rubble at night, attacking any nearby people. The player, as one of the survivors, must get to the evacuation center on the other side of Carver City.
The game has a free-roaming structure like Dead Rising, where you run missions, collect supplies, and survive dangerous disaster scenarios during the day and must fend off the creatures at night. You can also barricade buildings and create new items by pulling apart and combining old ones. You can, say, take apart the stock of a shotgun and combine it with some gauze to make a leg splint, or duct-tape a flashlight to the barrel of a gun.
Along the way to the evac site you can choose to rescue people from various situations; doing so will net you experience, new items, and other rewards, as will surviving events like earthquakes, aftershocks, building collapses, and so on.
Anyway, enough rambling. Obviously, this game is way too ambitious for me to make, but I've written down the ideas so that, if I ever become a professional game designer, I'll definately make this game.