Barren Realms Elite or BRE is a multi-player bulletin board system strategy game.
Barren Realms Elite is a 25-player strategic war game originally by Mehul Patel. The setting is in the future -- nuclear destruction has spread throughout the planet, and now only a vast barren void exists. As a baron under a great king, you must expand your barony throughout the planet and become the ultimate baron.
One feature of the game was the ability for a bulletin board system to compete against other BBSs. Each BBS would function as its own distinct planet in a universe of planets, where the universe comprised all of the BBSs that agreed to host the game together. Messages and attacks would travel from planet to planet on a regular basis as the BBS systems called each other to transmit and receive data.
The focus on inter-BBS play completely changed the game dynamics, and both BRE and SRE continued to be developed for several years. In modern times, Barren Realms Elite has managed to maintain a fair number of players, most of whom connect to BBSes via Telnet in order to play.
The game was based on Solar Realms Elite (SRE), and is considered by many to be SRE's successor.
Source: Wikipedia, "Barren Realms Elite", available under the CC-BY-SA License.