jingle mail n. building or house keys sent by mail and unexpectedly received by a mortgage-issuer from someone who can no longer make mortgage payments and chooses to relinquish control of a property. (source: Double-Tongued Dictionary)
Further reading
While reading Great Expectations (Bookshop|Amazon) by Charles Dickens, a listener in Arlington, Texas, is surprised when one of the characters inherits some money, which Dickens describes as a cool four thousand. Were they really using cool that way...
An anadrome is a word that forms a whole new word when you spell it backwards. For example, the word “stressed” spelled backwards is “desserts.” Some people’s first names are anadromes. There’s the girl named Noel...
The phrase “jingle mail” appeared in the New York Times of 5/10/08, p. B1, in an article entitled “Mortgage Holders Find It Hard to Walk Away From Their Homes.”
URL http://www.nytimes.com/2008/05/10/business/10housing.html?em&ex=1210564800&en=df014084fed21ba5&ei=5087