Floating shelves look fragile to the naked eye because of the way they sit on the wall. All the workings of the brackets are hidden so it seems as though they are floating there on the wall. In reality they are usually much stronger than other types of shelves which are supported with traditional brackets and screws.
A great idea for a decoration would also be a wreath. This is an item that you can make when you have a bunch of small driftwood pieces but no idea what to do with them. The wreath is really simple to make. You just need to glue together the driftwood pieces to form a circle. Hot glue is preferable in this case. The wreath would make a nice decoration for the entrance door or for the wall.