It's still a color, it's just very subdued. And we're really into it lately, considering all sorts of charcoal-colored accents for the home. These are just a few we have in mind:
The front door: Both inside and out. It's neutral and serious, but not nearly as stodgy as black.
Stair risers: Whether in a print like this henna-inspired design or in a solid, we like the muted quality of gray on this vertical surface (and it won't mar as noticeably as the more traditional white).
Window boxes: In a naturally charcoal-colored material like zinc. These rectangular planters from Crate & Barrel are nice and well-priced.
Walls: This is what started our current charcoal kick.
Cabinets: Dark gray kitchen cabinets look a little bit country and a whole lot sophisticated.