Do you mean the Kaleidoscope block?
http://tlc.howstuffworks.com/home/ka...uilt-block.htm
Or a One Block Wonder/Stack & Whack quilt - using repeats in the printed fabric?
see the links given upthread
Or a Paula Nadelstern Kaleidoscope style quilt (the real deal) - using repeats with bilateral symmetry and mirror images?
http://www.paulanadelstern.com/