A very interesting project, of which until today I'd had no prior knowledge, released a status update on the 8th. What is shown is a small SBC in a casing with some custom circuitry. The back of this casing has magnetic connectors allowing the attachment of arbitary accessories in a grid. Each accessory enables some new functionality. These accessories can range from buttons, dials, and lights to cameras of varying types, and even to IO devices and whole extra CPUs. The project is called Pockit, and seems to be extremely well thought out.
From what I can tell this a one man project so far, and the results are astonishing. There are default configurations for each acessory. If you add say: a microSD adapter, a button, and a camera and you proceed to press the button, a snapshot will be taken from the camera and saved to the microSD card... without prior configuration being truly required. The devices does have a management interface allowing for customization of actions, changing of defaults, and other settings and configurations. If you just want to see it in action the demos are here.
It's absolutely worth a look!