ENC28J60 Ethernet LAN Network Module
These things are a blast! Setting up a tiny server is surprisingly easy to do. I have some code and instructional videos here:
Code and Video Instruction set 1.
Code and Video Instruction set 2
The board 25MHZ crystal.
The network interface board HR911105A.
3.3 V and 5V power
Size: 58*34*17 mm