Dumpster Dive

A dumpster dive happens when someone intentionally searches for something in someone else's pile of refuse.

Someone on a dumpster dive may be looking for things to reuse or to sell to recyclers, improperly destroyed confidential information to misuse, or evidence of a crime.

May lead to the discovery of a Grail in the Garbage. Not to be confused with Trash Landing (a pile of refuse breaks one's fall).

Live Action TV

 * Several times in CSI, Law & Order, and other Police Procedurals. (Let CSI fans expand this.)
 * Steptoe and Son and its American counterpart Sanford and Son are about "rag and bone men".

Real Life

 * When a company replaces old computers with new computers, geeks will search the company's dumpster for equipment.
 * Freeganism, a sustainable living philosophy that includes dumpster diving to not waste food.
 * Dumpster diving is a living in Manshiyat Naser, whose residents live off Cairo's garbage, making it one of Cracked.com's The 6 Weirdest Cities People Actually Live In.
 * Identity thieves searching for people's personally identifying information in dumpsters, and hackers searching for passwords and other information they can use to break into corporate or government computers, are part of the darker side of dumpster diving.
 * This trope is Older Than Radio: In 19th-century London, dumpster divers were called Rag-and-bone men. They still are, in fact -- after a brief disappearance during the middle-late 20th century, rag-and-bone men are enjoying a renaisssance in the age of recycling.