There are a lot of R2D2s out there are likely outside of the realm of reality/budget for most of us. R2 projectors, garbage cans, and mailboxes. Thinkgeek's outdone themselves with this cheap, mini R/C R2D2, that spins as it reverses, drives forward, flashes his Red LED, and and whistles accordingly. The remote control is in the shape of a lightsaber, too. $30, which is a fraction of what your unopened action figures are worth.
Seriously, keep making these. I can't get enough of em.
Mini R2D2 [Thinkgeek]