The ATtiny85 based mini development board is similar to the Arduino, but cheaper and smaller (ofcourse a bit less powerful).
With a whole host of shields to extend its functionality and the ability to use the familiar Arduino IDE, this board is a great way to jump into microcontroller electronics.
Support for the Arduino IDE 1.0+ (OSX/Win/Linux)
Power via USB or External Source
Onboard 5V Regulator
6 I/O Pins
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
Package Contents: 1 x development board
Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.