MSNBC.COM September 08, 2004 BY LEONARD DAVID They have become legendary in UFO circles. Huge, silent-running “Flying Triangles” have been seen by ground observers creeping through the sky low and slow near cities, and quietly cruising over highways. The National Institute for Discovery Science, or NIDS, has cataloged the Triangle sightings, sifting through and combining databases to take a hard look at the mystery craft. Based in Las Vegas, NIDS is a privately funded science institute with a strong research focusing on aerial phenomena. The results of their study have just been released, and lead to some unnerving, puzzling conclusions....