The Pilea peperomioides is also known as the Chinese Money Plant, Pancake, or UFO Plant. My favorite nickname though, is The Friendship Plant.
Native to China, it is believed that a Norwegian missionary took cuttings with him when he returned home in the 1940s. And the way that this plant spread in popularity was through the sharing of its pups (babies). This is also why this plant is also known as the Friendship Plant.