I've thought about using command block magic to fling tnt out of it so it looks like it's errupting... but that might lag people too much xD
You know how when a TNT. Explodes blocks go flying? You could do that with non-flowing lava and stone.
I'm making a colosseum on it (which may be spawn). I would love to make a full town and harbor and all... I'll try to make a good place to go get them good Unitus