Remember Google's Project Ara modular phone concept? It lets you swap out individual components like the camera and processor without having to upgrade to a brand new device.
Blocks is a smartwatch that looks set to do the same by letting you clip together combinations of different modules to create the ideal smartwatch for different situations. And, sensibly, most of those modules slot together to form the bracelet, so the main body doesn't need to be much more complicated than that of a common or garden smartwatch (although you can swap the screen out).
Modules range from extra batteries to screens, cameras, processors and GPS radios. If you're heading down to the gym then you might opt for a heart rate sensor and pedometer, for example.
If you're heading off on a long hike, however, you might want to add in an extra battery and GPS module to make sure you don't end up lost and stranded.
An 8MP camera and a SIM card for uploading snaps directly from your watch might be the better choice for a night out, especially if you're prone to leaving your phone in the thieving embrace of a black cab seat.
Like modular phone concepts, the possibilities are vast, and very exciting - but Blocks is currently only in the 'working prototype' stage.
While the Blocks team is aiming to launch device in the first half of 2015, it's set to debut on a crowdsourcing site soon to get the ball rolling - so stay tuned.