The Raspberry Pi has a knack for bridging the gap between different technologies but, in this project, it's combining the power of multiple routers into one connection point. This setup is referred to as a bonded router by its creator, Jona, and operates using a platform called Speedify.
The best Raspberry Pi projects tend to come out of necessity—often providing a solution to a specific problem. According to Jona, he was tired of the bandwidth limitations of rural internet and decided to merge multiple sources into one, stacking the available speed. Before this project, his network speed was capping around 2 - 5 Mbps but now it reaches up to 120 Mbps.
The Raspberry Pi is responsible for distributing network traffic between four individual internet access points (in this case, two LTE lines and two 5G lines). Jona also included a DSL failsafe to act as a backup in the event the bonded router connection drops.
If you'd like to recreate this project, you can download Speedify from the official website. It's available for Linux machines like the Raspberry Pi but also on Windows, Mac, iPad and Android devices. In Jona's setup, he's using an 8GB Raspberry Pi 4 with a 4G LTE HAT. It also has a USB hub connected to a 4-four gigabit Ethernet adaptor and a 5-port Netgear gigabit switch.
Read more about this project in detail on the project thread at Reddit and be sure to follow Jona for more cool Pi projects.