Ever tried planting perennials? I put potatoes, artichoke and onions in my garden probably 5 or more years ago. They come up again every year. In fact, they're coming up again in the Spring is what signals me that it's time to get out there and get ready to put in the annual things.
Here in SoCal, tomatoes volunteer too. I'd rather choose nursery varieties since we can get heirlooms at the nursery but this year I'm letting one of the volunteers grow out just to see what it turns out to be.