Revan by Drew Karpyshyn

This book is set way back in Star Wars mythology--thousands of years before the events of the movies. It brings together the stories of Scourge, a Sith Lord seeking more power in the Empire (of that time) and Revan, a Jedi who betrayed his cause and lost his memory and now knows there's something ugly on the edges of the galaxy. The story ties into a video game, but it wasn't too hard to pick up what was going on. I thought it did a better job of filling in what was happening in a galaxy far, far, away a long time ago than in developing its characters (although those familiar with the game might not find them as sketchy).