This is a really cool alternative to a snow globe. The crystals continually dissolve and reform, and you can direct their growth by positioning it upside-down, sideways, and more.
This is a great kit. It comes with all kinds of tools for working the clay, including rollers and hammers. I've used this kit with my kids and we all like it. The clay is more like modeling clay, but lasts longer than most. You could use the same tools with playdough.
I would have loved one of these when I was a kid! What a cool toy! I wonder if the "siren" has a volume control, though. Setting up the beams so that they all connect properly could be a lot of fun.