A man's home is his castle, be it a mansion or, in this case, OPod. Mr Jonathan Kong, a designer director at James Law Cybertecture, shows how anyone may be ruler of his own space inside the OPod Tube House, which was displayed at the DesignInspire exhibition in Hong Kong. The unusual house is an experimental low-cost, micro-living unit constructed out of a concrete water pipe. Several may be stacked up to form fast and cheap housing. The idea is aimed at easing Hong Kong's affordable-housing problem.