I suspect the answer to this is a resounding no, but thought I'd ask anyway. Can you create new blocks using a plugin for bukkit? If not can you change the textures on an existing block? Again I'm guessing no, that this is all client side, but thought it best to ask. I would like to see some more decorative blocks in MC, but if neither of these are possible I might look into the texture packs and see if I can change the texture for an existing but underused block into what I need.