ATtiny85 Mini USB Development Board

The Digispark is an Attiny85 based microcontroller development board similar to the 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 IDE the Digispark is a great way to jump into electronics, or perfect for when an is too big or too much.

Features:
– Support for the IDE 1.0+ (OSX/Win/Linux)
– Power via USB or External Source – 5v or 7-35v (12v or less recommended, automatic selection)
– On-board 500ma 5V Regulator
– Built-in USB
– 6 I/O Pins (2 are used for USB only if your program actively communicates over USB, otherwise you can use all 6 even if you are programming via USB)
– 8k Flash Memory (about 6k after bootloader)
– I2C and SPI (vis USI)
– PWM on 3 pins (more possible with Software PWM)
– ADC on 4 pins
– Power LED and Test/Status LED

See this Tutorial 

Package Includes:
1 x Digispark ATTINY85 Mini USB Development Board