In a clever twist on sustainability and tech reuse, two innovators at the University of Tartu in Estonia have devised a system that converts old smartphones into a compact “data hub” or mini-data-centre. Instead of contributing to the growing mountain of unused devices, these phones are linked using a 3D-printed frame and auxiliary circuitry, repurposed into a low-cost, portable cluster.

The prototype has already been tested in real-world scenarios: underwater deployment to monitor marine life, and urban use-cases like installing them at bus stops to track passenger flow. With just around €8 per device to repurpose, this approach offers a surprising combination of affordability, flexibility and ecological benefit. With just around €8 per device to repurpose, this approach offers a surprising combination of affordability, flexibility and ecological benefit.

Crucially, the project challenges traditional notions of computing infrastructure by focusing not on raw brute-force power but on adaptability, reuse and sustainability. Old phones, once considered obsolete, are now reframed as valuable technological assets. The innovation invites a broader rethink of product life-cycles: rather than toss away functional hardware, we can extract new value, reduce resource consumption and mitigate e-waste. The message is clear: technology’s future isn’t just about what’s new, but also how we reuse what we already have.