I'm curious about your experiences with trying foods not generally cultivated (not in stores, not from buying the seeds and growing, etc.).
Edible plants are all around us, native, recently escaped cultivated and weeds. From wasted fruit and nuts from trees on residential lots to wild greens and roots, so many more people could be better fed and kept healthy.
I've taken classes and been on field trips around Portland Oregon with John Kallas, author of "Edible Wild Plants." It's amazing to me how many edible wild plants, including weeds, are all around us, many of them more nutritious and flavorful than the cultivated counterparts. Sautéed nipple wart in a tortilla or two can make for a fine tasty meal, even though it doesn't sound very good. Purslane, dandelion (greens, root, flower, etc.), queen anne's lace, wild sweet peas, wild mustard (greens, seeds) are just a few of the weeds that grow across most of the USA and can be quite tasty nutritious when the right part of the plant is taken at the right time and prepared properly. The poorer the growing conditions (bad soil, too dry and/or hot, etc.) the more likely the plant will be tough and bitter. So some weeds taste worse from growing in bad places.
Aside from these examples, there are thousands of edible plants. I'm trying to draw attention to this in an effort to get more people involved in the effort to increase mankind's list of plant ingredients. In many cases we have historical records of people eating certain plants. Each may have unique anti-nutrients, toxins, healthful phytochemicals, bountiful nutrients, etc. that we have not yet determined in them. And for historically eaten plants not currently being eaten, we don't know if the plants they ate are identical to the same species we find today, as plants adapt change over time and location. Chemical analysis of plants can be costly enough for one sample of a plant just to look for known nutrients. But finding each unique phytochemical (both beneficial and harmful) can be even more expensive.
I've been researching ways to determine nutrient and various phytochemical amount estimates accurate enough to be useful for determining a particular plant food's health benefits and culinary potential (across a myriad set of potential methods of preparation). Aside from agricultural research designed to improve animal feed stocks, I haven't come across much research in the United States or Europe along these lines, though there are many growing databases on edible plants, foraging, etc. Africa and Asia, especially India, where poverty and hunger are particular motivators, appear to be areas with some of the most active research into the nutrient and anti-nutrient analysis of non- and less-cultivated plants. Vegans and non-vegans alike will benefit from a wider variety of healthful plants, especially if they are hardy and grow without human intervention.
I'm sure there are many more talented people out there who could help with this effort. I'm a scientist/engineer/inventor/musician who sees great potential in natural edible plants studied with the aid of the ever growing free online bioinformatic tools for analysis and culinary sciences for maximizing flavor and healthfulness. I've got a few sets of research project results which I'm hoping to publish in the not to distant future. Meanwhile, I put a prototype software application for nutritional, taste and health factor analysis online via recipefactory.net. It's a work in progress, but many people have found it to be useful for creating recipes.