Twister

a.k.a. Wooden Screwball, Clever Toys Natural
Made by Clever Toys, 2008.
(wood, 3.5 inches diameter by 2.9 inches high)

This is a simpler version of the Rainbow Puzzle described on Jaap's Page, where the loops have only eight balls instead of ten (and the center ring moves only one row of balls) and when solved all balls in a loop have the same color.

Solution: Using two adjacent circles as scratch, it is easy to solve the other two. So without loss of generality assume that the puzzle is now solved except that in two adjacent circles, the red and black balls are mixed up. Rotate a black ball in the red circle to the center section, rotate the red ball in the black circle to one position away from the center section, spin the middle one position, rotate the black circle one unit, and spin the center section back. Keep repeating this step until solved. Note that this solution allows one to put the circles in any order.

Further Reading
Jaap's Page, from: http://www.jaapsch.net/puzzles/rainbowp.htm