Industrial designer Jacques Averna, one half of Paris-based design firm Canel-Averna, which specializes in signage, created this sign that uses no electricity. Instead, it uses dots made of polymethyl methacrylate, a transparent thermoplastic that, here, is used to reflect nearby streetlights:
I could find no more information on this, and at press time Canel-Averna's website appears to be down.
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