tape bomb
n.— «Wall Street traders like to call unexpected news events “tape bombs.” The terminology presumably dates back to the days when the physical flow of ticker tape delivered the latest ups and downs of stock price movements. Last week, some market-moving tape bombs included the announcement on Tuesday by the nation’s 10th largest mortgage lender, American Home Mortgage, that it could no longer fund home loans and might be forced into bankruptcy, and the acknowledgment on Friday by Bear-Stearns” chief financial officer that current bond market was “as bad as I’ve seen it in 22 years.”» —“Wall Street waits for the next ‘tape bomb’” Salon Aug. 6, 2007. (source: Double-Tongued Dictionary)