Emeryth designed a breakout board for the Stellaris ARM Cortex 3 microcontrollers from Texas Instruments. It supports either LM3S3748 (USB device/host) or LM3S6938 (Ethernet). The LM3S6938 requires and additional Ethernet daughter board. He based his design of Texas Instruments evaluation boards. You can download the source files from his site. Via the forum.