Indigenous to Okinawa, awamori 泡盛 is a distilled alcohol similar to Japanese shochu. However, it is made with a long-grained, Indica crushed rice and a different mold for fermenting, giving it a unique flavor. Most exported awamori is 50 proof (25%), but the kinds you find in Okinawa are stronger, usually 60-86 proof (30-43%) or higher.
It is aged in clay pots for a mellow flavor. Ones aged over 3 years, locally referred to as kusu, is especially prized. Traditionally awamori is served with water and ice, but some people drink it straight. Now there are a variety of cocktails made with awamori.
A great video on the process of making Awamori at Zuisen Distillery can be seen here. It has English captions and goes through the entire process.
Why not try some on your trip to Okinawa?