"Sago is a starch extracted from the pith of sago palm stems. It is a major staple food for the lowland peoples of Papua New Guinea and the Moluccas. It is traditionally cooked and eaten in the form of a pancake and served with fish.
Sago looks like many other starches, and both sago and tapioca are produced commercially in the form of "pearls". Sago pearls are similar in appearance to tapioca pearls, and the two may be used interchangeably in some dishes. This similarity causes some confusion in the names of dishes made with the pearls."
And yet I bought "Seed Tapioca (Sago)", so clearly McKenzie's thinks they are the same thing... go figure.
Either way it all sounds fairly exotic for for something my brain thinks of as boarding school food...
I haven't made anything with my tapioca yet, as every time I read the packet the first instructions is to 'soak the Tapioca for 24 before use', which really doesn't lend itself to a spur of the moment thing.
However, Mrs Beeton doesn't have that as an instruction so I may just give it a burl...
Stand by for some tapioca pudding real soon.