Fable 3, that long-fogotten RPG of a game is currently free on the Xbox Live Marketplace. All you gotta do to snag it is contained within these three steps: head over to Fable 3's game page, you must be paying with Microsoft points, not a credit card; then, once you land on the confirmation" page, you'll notice that the game is "free."
Update: Users are reporting it is no longer available free. Possibly a glitch. Stay tuned for more E3 coverage.