Homemade R2D2s
The Bay Area R2 Builders showed off four fully-functioning R2D2 units at Maker Faire. They cost around $10,000 to build, and take a couple of years of work. http://www.wired.com/video/builders-construct-10000-fully-fun...
https://www.neatorama.com/2009/06/01/homemade-r2d2s/