ENC28J60

Adds a wired Ethernet connection to a microcontroller over SPI, at a noticeably lower cost than a W5100 shield. The trade-off is worth understanding before you choose: the ENC28J60 provides only the physical and MAC layers, so the TCP/IP stack runs in your microcontroller's memory using the UIPEthernet library. That consumes a significant share of an Uno's limited RAM. If your project is memory-tight, a W5100 module with a hardware stack is the easier path despite costing more. Wired networking at lower cost than W5100 modules; Reliable connection where WiFi is unreliable; Compact module suits enclosed installations; Standard SPI interface, few pins needed