High school robotics team builds world's smallest, cheapest network switch
High school team Murex Robotics builds the world's smallest and cheapest network switch, mrxSwitch v2.0, for $7 with 5 Ethernet ports.

Murex Robotics, a high school robotics team from Phillips Exeter Academy in New Hampshire, has created the world's smallest and most affordable network switch. The device, called mrxSwitch v2.0, measures just 44.9mm x 42.2mm and costs only $7. It offers five 100Mbps Ethernet ports, which are sufficient for the underwater rovers and robotic submarines for which it's designed.
The mrxSwitch v2.0 employs compact 4-pin Molex PicoBlade connectors instead of traditional RJ-45 ports to fit into tight spaces, such as the interiors of waterproofed robot shells. With components like a dual-port transformer and a high-performance unmanaged switch IC, Murex Robotics optimized the device for both size and cost efficiency.
Despite its small footprint and low cost, the mrxSwitch features robust functionality, including a 4-layer PCB for minimized noise and IEEE 802.3 Ethernet compliance. Impressively, the project is fully open-source, encouraging makers and hardware enthusiasts to study or replicate the design using the provided GitHub resources.