I don't know the correct "Ride of wotsit" / "Battle of Thingy" title for this bit in LOTR - and to be honest i can't remember which film it is, 2nd or 3rd one though. But when Gandalf rides out alone with his staff lit up to fend off the flying wraiths while the army gets inside the city. Awesome scene, seem to remember the sheer lack of music at one point gave it an amazing atmosphere.
Also, Trinity on the motorbike going against the traffic in Matrix Reloaded, amazing spectacle.
Obi Wan vs Darth Maul vs Qui Gonn Jin, in Phantom Menace, pretty much redeems the entire film.