i have always read that you can only get one domain in a scene, but recent mucking about with the smoke sim proves otherwise! granted a domain will block the view of another domain if it obscures it in the camera render, but if the domains are aligned so they dont cross you can have as many domains as your memory can handle!
oh, what is actually even cooler… i discovered you can have multiple domains… on a single object!
just thought i’d share
though, i’m probably the last to know this.