Research (and response here so far) says that it is an American thing and very uncommon in Europe. We did find some UK websites talking about pet hedgehogs, though, which informed us that the trend has begun to be imported to this country (well, Woody's existence also proves that!) - according to one website, published 2008, pet hedgehogs were being sold for £160 and there was a waiting list. Ours came free! Kitting him out hasn't been and will continue not to be cheap, though.

Pets, eh! Small's late lamented hamster was so much easier...