[6] Porcupine has been noted for its unusual place name,[7] and for its designation as the unofficial capital of the unrecognized Republic of Lakotah.

According to the United States Census Bureau, the CDP has a total area of 9.5 square miles (24.6 km2), all land.

Porcupine is home to KILI (90.1 FM), a non-profit radio station broadcasting to the Lakota people on the Pine Ridge, Cheyenne River, and Rosebud Indian Reservations, part of the Great Sioux Nation.

Broadcasting to the Lakota people on the Pine Ridge, Cheyenne River, and Rosebud Indian Reservations, part of the Great Sioux Nation.

It started broadcasting in 1983 as the first American Indian-owned radio station in the United States.

At the end of 2008, KILI announced on its website that the station would be powered by a wind turbine.