FEZ Mini is a tiny board running Microsoft .NET Micro Framework. This means, you can write code with much more efficiency using C# programming language under free Microsoft Visual C# express. The pinout is BasicStamp2 compatible. Includes USB cable.
Many libraries are already included like FAT file system on SD cards, threading, UART, SPI, I2C, GPIO, PWM, ADC, DAC and many more.

Note: Unlike FEZ Domino, FEZ Mini doesn't have USB host; therefore, it can't be connected to a USB Memory stick or other USB device. But, it has USB client port to connect to a PC.
Many libraries are already included like FAT file system, threading, UART, SPI, I2C, GPIO, PWM, ADC, DAC and many more.