The phrase ' raining cats and dogs' comes from Old Norse mythology and is related to Odin, the storm god;A ' red herring' is a distraction from the main issue, and comes from old fox hunting traditions;The saying ' don't count your chickens before they hatch' was first found in Aesop's writings;The phrase ' gravy train' means to doittle work for aot of pay, and originated in the 1920s.