Physarum polycephalum , better known as "The Blob", is facinating to watch and only takes a couple days to develop! Just add water, simple to grow, no special cleaning or sterilizing is required. Makes the perfect last minute science project for school and a great gift for any occasion.
It is not an animal, it is not a plant, and it is not a fungus.
Acellular slime molds or myxomycetes popularly known as "Blobs". A protist with diverse cellular forms and broad geographic distribution. The “acellular” moniker derives from the plasmodial stage of the life cycle: the plasmodium is a macroscopic multinucleate coenocyte shaped in a network of interlaced tubes. This stage of the life cycle, along with its preference for damp shady habitats, likely contributed to the original mischaracterization of the organism as a fungus.