Organization called League of Entropy is working on providing decentralized randomness beacon. Software implentation is called drand.
League of entropy runs public pool where anybody can get high quality randomness. Entropy is collected from high quality randomness sources, such as lava lamps. Pool endpoints are listed here.
Here you can see pool metadata. Randomness is 32 bytes long and its changing every 30 seconds. You can get not only current randomness but also all past numbers. Current randomness value can be seen here.