Credit: Vincent Auyeung (G)

Students check out the handiwork of Charles Z. Guan '11, who wanted to strap a set of large nickel-cadmium batteries to something--anything. He settled on motorizing a shopping cart, which is theoretically capable of reaching 35 miles per hour. The cart, which also boasts regenerative braking and a stereo sound system, earned Guan a ticket from the Cambridge police for operating without a helmet.

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