Eric Weiner reports despite enduring their worst recession in more than 50 years, many Japanese consumers are willing to spend gobs of yen on pets. Pet stores are enjoying a major business boom. Dogs seem to be the domestic animal of choice, so pet entrepreneurs are cashing in on all kinds of pet accessories, including doggie toothbrushes, conditioners and 85-dollar doggie kimonos. For busy urban dwellers, Sony has developed AIBO, a 25-hundred-dollar dog robot of uncertain gender. It can fetch a ball and bark, but AIBO is programmed never to bite the mailman.