I experimented with this last year for the first time and had amazing success. I will definetly be expanding on this idea this season. The trick is to use smaller varieties, water twice per day during the dog days of summer, foliar feed weekly (50% rate), and apply a side dressing monthly to boost soil.
This is an upside down Cream Sausage Tomato, with Nasturtium growing out the top.
This was an upside down Green Sausage.
This variety is called Black Cherry. It was both my first and last tomato picked. It produced prolificly all season! I saved the seeds (which means it passed all test of deliciousness).
Saving Tomato Seeds - continue improving your own selection every year, by chosing the biggest, earliest, etc (whatever charecteristics you value). Mark that tomato with a red flag, so you don't pick it and eat it. You need to leave it on the vine untill it is way over-ripe. Then squeeze the seeds and all other parts into a glass, let it ferment for a few days, then rinse and dry throughly, then store till next year.