There are plenty of interesting bikes to be seen at the North American Handmade Bicycle Show in Sacramento, California, this weekend. This Olivetti bike (called the Wopcycle) looks like three different bikes depending on your angle of view. From the right side, it looks like a green bike. From the left side it looks like a blue bike. From above, it looks like a blue-and-green bike. Initially, the whole bike was painted blue; then the right side was given a coat of yellow pigment on top of the blue, and that made that side look green. Interesting stuff.