$59 Mini-router supports Ubuntu Server and Debian 11
The E25 also provides access to up to 26x GPIOs supporting protocols as 3x UARTs, 2x SPI, 1x I2C, 1x I2S/PCM, 1x CAN, up to 6x PWM, 1x ADC, up to 17 GPIOs, 2x 5V pins and 2x 3.3V pins.
Other peripherals present in the E25 include one USB 3.0 OTG, up to 16x status LEDs and one USB Type-C used for power and serial console.
Documentation for this device can be found on Radxa’s Wiki, similarly Debian 11 and Ubuntu Server 20.04 images are located under Downloads. OpenWRT firmware for the E25 mini-router can be found in this GitHub from ophub.