The interest in growing tomatoes upside down seems to have increased over the past year or so. The commercial containers sem a bit flimsy relative to cost. This article offers a superior DIY system - http://www.seedsofknowledge.com/tomato2.html
Someone else suggest a further modification in order to grow varieties with larger fruits. Use a regular tomato wire cone and bent the bottom wires into eyelets. Insert through the grow hole and the inverted shape will give support to the plant.
Yuska
Topsy Turvy
Great idea. I will try this. I am running out of room for tomatoes because I keep planting roses and peonies.