This is a stackable nail polish stand, each tray holds about 4 bottles of nail polish. You can print as many parts as you need to make a rack as large as your collection. This rack is featured at my girlfriend's nail blog with a great description and with many many more pictures at http://www.nailandpolish.wordpress.com.
The rows are connected by M5x8mm screws and matching nuts. The legs are only needed every other row and due to a rather dynamic design process the rear leg has a front and back side, Yes I should have just made it the same but its not. You may need to clean out the interlocking section a bit with a sharp knife. Your printer will also need to print about a 45 degree overhang.