I saw one on ebay just yesterday. It may still be there. Other wise I see semi short tanks with stands on Craigslist ALL the time. I want one but cant justify it to my husband because well.... I dont have frags lol.
When peoples corals and mushrooms and what not over grow they trim them just like house plants.
There are tanks that are more shallow maybe 8-10 inches so you can put these trimmings in and they will grow into a whole other colony and you can sell or trade them.
Its just a different tank to put more stuff so your main tank doesnt over stock.