what do you mean by 'key charger'?
I thought that this idea was genius when I first saw it:
(this is an ebay link to one of the cheap e-cigs)
My buddy bought one of these a few years ago, and although the e-cig itself sucks, the charger/case combo was awesome. The charger is built into the box itself, the batter screws into the box, which is made to look like an analog cig box. It has room for spare carts, an extra battery, and another atomizer. I was hoping a quality company might want to go in this direction too.