The opposite of shoplifting, shopdropping is covertly placing merchandise on display in retail environments.
For instance, Banksy altering the Paris Hilton debut album and leaving it at the record store to critique and politicize its message, or the Barbie Liberation Organization swapping the voice hardware of Teen Talk Barbie and the Talking Duke G.I. Joe doll and returning the dolls to the shelves. (Instructions here.)
A new project from the Anti-Advertising Agency is PeopleProducts123. From the Web site you can download PDFs of new packaging for products, print them out, color them in, and place them in your local store. The improved packaging featuring images and stories about the workers who make them.
Participants are encouraged to upload their images to Flickr, tagged peopleproducts123. See a video about the project here.