Ad campaign: Heavy

The client is creating a conceptual ad campaign on the theme of "Heavy." We don't know anything about the service or product offered; the client claims that it will bias our image selection. They are looking for weighty images that will evoke the "Wow, that's heavy" response from a viewer. The client is not keen on photos of heavy people ... unless you are able to make it tasteful. Note that heavy refers to weight and mass, not seriousness.