I just read about a house that had a "busybody" What is a busybody?
Solution 1:
From the printed supplement to the OED:
busybody.... a mirror attached to a building, reflecting a view of the street, etc. U.S.
Solution 2:
The "Philadelphia Busy Body" was common on houses 100-200 years ago. The series of mirrors allowed the lady of the house to see a street vendor coming down the street and stop him with his cart. If she didn't see the street vendor he would pass by her house and continue on. She might not get her fruits and vegetables for that day