If you've ever had to move heavy outdoor furniture, you'll agree that this makes plenty of sense. The Mobile Bench was designed by Dutch artist Rogier Martens. Instructions for making your own are illustrated. http://www.rogiermartens.nl/projecten/mobiele-bank/ -via the Presurfer
Nice, but hardly new. Kew Gardens (at least, I think it was Kew - somewhere Londonish, anyway) had them well over 100 years ago.
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