dumpster diving

1. The practice of sifting refuse from an office or technical installation to extract confidential data, especially security-compromising information (dumpster is an Americanism for what is elsewhere called a skip). Back in AT&T's monopoly days, before paper shredders became common office equipment, phone phreaks (see {phreaking}) used to organize regular dumpster runs against phone company plants and offices. Discarded and damaged copies of AT&T internal manuals taught them much. The technique is still rumored to be a favorite of crackers operating against careless targets.
2. The practice of raiding the dumpsters behind buildings where producers and/or consumers of high-tech equipment are located, with the expectation (usually justified) of finding discarded but still-valuable equipment to be nursed back to health in some hacker's den. Experienced dumpster-divers not infrequently accumulate basements full of moldering (but still potentially useful) {cruft}.

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