It's not necessarily what you are thinking about but I love the idea of women using a obesity belt.
spinalbrace.com/obesitymaternity/obesitybelt.htm(Sadly, I could not find a page where they have a female model wearing the obesity belt)
Perhaps not really squeezing the belly but more giving it support and preventing it from hanging so that the woman looks fatter, I think it would possibly improve or prevent back pain in big bellied women.
My dream woman would use a obesity belt and have most of the belly outside of her pants.
An alternative to a obesity belt would be to just have a tight shirt to give support to the big belly.
