ShowCaseStandalone

Description
ShowCaseStandalone is a simple plugin that allows players to put items on display on top of blocks. It does not require you to have the item in question, you simply need to know the item ID

Information
SCS responds only to the numerical item IDs or Minecraft's default phonetic names such as IRON_SPADE or DIAMOND_BOOTS. These IDs can be obtained by holding an item and typing /iteminfo or /iinfo or by consulting an outside resource.

Additionally, there is a bug with SCS that sometimes makes duplicate items float on your displays. This can be fixed by leaving an area and returning. There seems to be nothing that can be done about this right now.

Links
Bukkit Dev