Excellent project originally made by George Chiou (http://www.thingiverse.com/ShinWeiChiou/about), I'm glad to present you my Miniplan 5.1 (renamed here MiniNet's for some reasons ) .
For this project you will need about 130-140 € for the stuff and some filament.
I've decided to make the IronMan body (another body is Proposed by ShinWeiChiou ) with the moving head .
I've already bought a raspberry PI Zero to make the robot "brain" and some cool stuff (Internet connection, speech recognition , voice synthesis , and more ... )
EDIT 08 Jun 2016 :
My battery is too big for the original Miniplan model, and the control board too. It result i have added 18mm to each body parts, i will post here the STL files soon !
Here, i'ts my ebay shopping list to make it :
And, 1x Raspberry PI Zero (5€), some Leds, wires, a Usb Wifi Key, a Usb Bluetooth Key, a Usb Audio Key, a microphone and one speaker.