The USS Pegasus (later the USS Tombstone) was a Star Trek chat sim under the command of Nathaniel J. Horn. The Pegasus began in 2001 as a sim in Trek Online. In 2003, the sim was one of several that left TOL to form the Rogue Fleet Simulation Group. The sim premise was similar to the USS Pegasus appearing in the Star Trek: The Next Generation episode The Pegasus, where a Starfleet ship by the same name was testing a prototype cloaking device. The sim met Friday evenings in an AOL/AIM chat room.