Source: http://www.journaldugeek.com/2013/01/21/r2d2-fonctionne-avec-un-raspberry-pi/

Crédits:

13 janv. 2013

This is a birthday gift I built from scratch for my girlfriend :)
The hardware is made of a broken Interactive R2D2 toy and a bunch of cheap parts purchased online. Inside, the little guy is powered by a Raspberry Pi running Rasbian.

Features:
voice control (in English and Chinese, using PocketSphinx)
face recognition (using OpenCV)
motion detection 
ultrasonic distance detection
audio message record and replay
sound play and TTS
rechargeable battery
wifi