From Nookipedia, the Animal Crossing wiki
The Recycling Bin is an object that appears inside the Town Hall in Animal Crossing: Wild World and Animal Crossing: City Folk, serving as place for players to discard and recieve unwanted items. It returns in Animal Crossing: New Leaf as a Public works project.
 Uses and Characteristics
The Recycling Bin holds the various items that the player and their neighbors have discarded. The player can take any of the items that he/she wishes to take out of the Recycling Bin, similar to lost and found. The Recycling Bin holds a large variety of items, including furniture, clothes, accessories, and pitfall seeds. However, these pitfall seeds aren't discarded by a neighbor, but are randomly computer generated. Every Monday and Thursday at 6am, all of the items found in the recycling bin are picked up, emptying the bin.
The Recycling Bin is a "Mother of Pearl" white. It's lid is a forest green color. On the lid is an oval with the same "Mother of Pearl" white color. Inside the oval is what appears to be fish bones in the same color of forest green.