Add Ethernet to your development board or Arduino with ENC28J60 Network Development Board Module from Tronixlabs.
This convenient module offers Ethernet connectivity to your projects using the SPI bus. Further thanks to the great price, it's the cheapest method to get your Arduino project connected to a network.
It uses the Microchip ENC28J60 SPI Ethernet controller IC - which is a 3.3V part. Thus you can use this module as a very cheap way to add Ethernet to an Arduino Due or other 3.3V tolerant board - however it does work with 5V boards - just power the module from the 3.3V pin.