Looking for a great second camera

I currently have a Nikon D800 as my main camera. But anyone who has used a larger camera like that, knows it's not the easiest to carry around. So I'm looking for a good quality, preferably pocketable camera. I recently bought the Sony NEX-5R, and with the 16mm pancake lens, it's good, but not quite pocketable. I was thinking of returning this for the Sony RX100, but was worried about image quality compared to the NEX-5.

Granted, since I already have a D800, I'm not looking for stellar picture quality. But it'd be nice to be able to carry something around with me, to events, or to Disneyland, where carrying a D800 will be a pain in the ass. I don't have any preference toward Sony, so if there is a better one out there, I'd be up for it. Thanks!