damn-really cute mobile USB battery charger
http://www.engadget.com/2009/07/01/energizer-usb-clip-to-charge-camcorder-dslr-batteries-via-usb/
Original Cart rider(video incl.)
http://www.engadget.com/2009/07/01/video-grocery-cart-morphs-into-electric-go-kart-insanity-ensue/