For several years there have been at least three groups on Flickr devoted to food items eating themselves:
Happy Ham--http://www.flickr.com/groups/happy_ham/pool/
Scary beings Eating Themselves-http://www.flickr.com/groups/autophagy/pool/
Cut Me Wicked Servant--http://www.flickr.com/groups/cut-me-wicked-servant/pool/

Farmers in rural NC use the honor system all the time for fruits and vegetables. Here's a photo of an honor system watermelon stand (not that the jar was full of money: http://www.flickr.com/photos/bunchofpants/33476006/

The melon I bought was one of the tastiest I've ever had.

These contraptions, called "slat mills" (or carpet mills if they used a loop of carpet for the running belt) are still in use by agility, flyball, frisbee and schutzhund trainers to keep their dogs fit and in good cardiovascular shape. They're also used a lot by the dog-fighting set, which gives them a bad name, but they are a great way to get a dog exercised if space or weather is an issue, and dogs who are properly trained to used them get really excited about running on them. You can pay $1,500 to $3,000 for a good one.