As promised, here is a picture of the other never-before-seen produce Amy found at the Billings Forge Farmers Market:
These things that look like teeny-tiny watermelons are Mexican Sour Gherkins. They are a type of cucumber, as you can see in this picture:
We ate them as-is, and they had a sort-of bitter (sour, we suppose), kind-of citrusy, cucumbery taste. We hope we find them again, because if we do, we'd like to pickle them, or put them in a salad, or even use them as a garnish for a Bloody Mary. Yum!