Like most vegetable gardeners I at times find myself plagued with a lack of space, so many things to grow and such limited space. Group your plants closer together and your quality as well as your yield will suffer. One solution is compact plants, plants that are bred to produce full size, premium quality produce on compact plants.
Tomato plants can be cumbersome so far as the space they consume. There are however a number of dwarf tomato plants that will produce full size fruits. Tomatoes that weigh in the ballpark of a pound each.
Much of the work on breeding these compact plants has been conducted by a group known as the Dwarf Tomato Breeding Project which has come up with about 70 tomato varieties that are compact plants but not necessarily compact fruits. Dwarf varieties, before the Dwarf Tomato Breeding Project were relatively rare, close to being unheard of. Today they are still fairly rare, but more readily available to the home grower.
A few I have tried and can attest to are Tasmanian Chocolate and Dwarf Sweet Sue
There are many others, some easier to locate than others. Victory Seeds carries many of these as does the Heritage seed market.