The Digispark is an Attiny85 based microcontroller development board similar to the Arduino line, only cheaper, smaller, and a bit less powerful. With a whole host of shields to extend its functionality and the ability to use the familiar Arduino IDE the Digispark is a great way to jump into electronics, or perfect for when an Arduino is too big or too much.
The DigiX has a 32-bit 84 MHz MCU, embedded low power Wi-Fi (b/g/n), mesh networking support, 99 usable i/o pins, audio output, USB on the go support, onboard EEPROM, on-board microSD slot, built in real time clock, and is 100% compatible with anything that works with the Arduino Due - no adapters, code changes, or special software needed!