The USPS has been photographing letters and packages sent in the US for tracking and security reasons since at least 2013. Under a pilot program called "Informed Delivery," the USPS is emailing to people photographs of the front side of their mail every morning before it is delivered to their home (not business).
PO Box users are not currently targeted as participants in the pilot. PO Box customers in certain Post Offices nationwide can use the existing Real Mail Notification ® service to receive a text-only message without images, via email, or SMS message. You can check with your local Post Office for more details.
The free service will send up to 10 black-and-white photos of mail per day. People who get more than that will be able to check their mail online in the same place they track their packages, according to the USPS fact page.
In 2015 the service was available in the New York City metro area, including the following three digit ZIP Code locations: NY: 100-119; CT: 066, 069. The service has been available in select ZIP Code locations in Northern Virginia since 2014 starting with the following three digits: 201, 220, 221, 222, 223, 226, 227. Expansion to other areas is being considered for 2016.
Great for finding those mailings physically delivered to the wrong house.