On prickly pears: Pick them when they are good and red with a good set of salad tongs, and wash them on gentle cycle no soap in your washing machine. The thorns will come right off. The jam tastes a lot like yellow tomato jam. You can steam the very young leaves and dress them with lemon juice to cut the slime, or chill them. They are reminiscent of green beans.
Chicory will be a small bright blue fringey flower which grows on a 1-2 foot high plant by the roadside. The blooms open in the morning only, and close in early afternoon.
I love Jerusalem artichokes, shepherd's purse leaves and seed pods in salads, sheep sorrel leaves and pods (looks like little okras), purslane, sassafras, blackberries, huckleberries, and any kind of nuts. I often mix my dried mint with dried wild rose leaves to stretch the supply. Dandelion greens are OK when they are young--I've eaten them when I could afford no other salad, or shredded them into ramen noodles.
If I could cultivate ramps, I would.