Not sure if anyone is interested in it but I have done some maintenance and trimming and wound up with a huge pile of this Purple Heart Wandering Jew plant (Tradescantia zebrina):
The cuttings have roots all along the stems basically put this in a pot and water it and you'll soon be overrun with it. It grows vertically up to about 6-8" then begins to crawl across the soil, rooting in other pots or dangling if you have a hanging basket. I'm not sure how long it will get, some of the cuttings are a couple feet long with leaves and roots all along the lengths. In a terrarium setting you can just cut it off a node or two above the soil and it will come back as you see above.
I will send a few clippings of other small plants and some clumps of moss to sweeten the deal.
I'm interested in other small terrarium species (under 12"), not necessarily carnivorous but must be warm to cool growing tropicals that can be kept indoors, preferably in terrariums.