I have grown cucumbers and zuchini very sucessfully this way. I was told that even cantaloupe will grow well, and even the smaller varieties of watermelons. The vines get bigger in diameter and sturdier as the vegs/fruits get heavier. I didn't have problems with the cukes and zuchini getting to heavy for the vines, but we picked the zuchini when they were about 8-10 inches long. Making slings sure couldn't hurt any for the cantaloupe.
Growing these types of veggies upwards really saves on garden space, and the back from stooping to pick them :D:D:D
Edit*** Just be aware that the vines and fruit/vegs have a LOT of weight, so make sure the trellis/fence can take the weight :wink: