Johannesburg, South Africa had six hundred high-tech traffic signals, each with a cellular modem and GPS chip. The idea was, if one malfunctioned, they'd call home immediately. Well, that plan isn't working out so well, because only two hundred are still in working order -- vandals ripped apart the rest to get at their SIM cards, causing traffic jams and accidents. Apparently, the government-provided cards are a ticket to unlimited free phone calls for the thieves -- at least until the individual devices are identified and their permissions revoked. The Johannesburg Roads Agency told the Mail & Guardian that the crime looks like an inside job, because only the SIM-equipped signals seem to have been targeted so far, despite looking visually identical. The damages are piling up, with the agency figuring it will require ZAR 8.8 million (roughly $1.26 million) to repair the four hundred signals currently out of order. Needless to say, the agency is looking at ways to better secure the traffic lights. We're guessing that switching to CDMA is probably off the table. Embedded SIMs, perhaps?