[cx500tc]

More info about the board itself here.

Board features (from the above linked page):
• ARM Cortex-M0 Core
• 48MHz, 128KB Flash
• 16KB RAM
• 32KB RAM for TCP/IP - Can be extended to system RAM
• Hardwired TCP/IP Core
• MII Interface
• ADC (8)
• GPIO (53)
• SWD (Serial Wire Debug)
• Timer/PWM
• UART (3)
• SPI (2)
• I2C (2)

External Ethernet PHY
• IP+ IC10GA
• Single Port 10/100 MII/RMII/TP/Fiber Fast Ethernet Transceiver
• Auto MDI/MDIX function
• Supports MDC and MDIO to communicate with the MAC

CMSIS-DAP
• LPC11U35FHI33/501, ARM Cortex-M0 Core, NXP
• Drag-n-drop programming
• USB Serial Port
• Easy to use C/C++ SDK

Connector
• USB Mini B Type
• Slim Size RJ45(with transformer)
• Arduino pin compatible
• SWD Header (1.27mm and 2.54mm)
• GPIO Header
• ISP Header

ETC
• 5V USB Power or 5V header supply
• 2 system SW - RESET SW, BOOT SW
• RGB LED
• Micro SD card slot

Retail is $29.90 USD + shipping; this board from me is $15 USD + shipping.

PM if interested.