Watermelon berries (Streptopus amplexifolius) are delicious and juicy, with a mild flavor. The stalk of the plant can also be eaten and has a flavor similar to cucumber. Although it has been a traditional food in its native range, I am not aware that it has ever been commercially harvested. It may be due to its preference for shady, wetter areas, or possibly because it is difficult to grow from seed.
This plant is known to grow across the circumpolar north. In Alaska it is more abundant south of the Alaska range, but I have observed it at Manley Hot Springs and have heard that it survives transplant into Fairbanks gardens.