The upcoming replay feature, of League of Legends, allows you to watch replays of recently played games. You may also download the replay, in a .rofl file, for later viewing.
This program takes a .rofl file as input and extracts out the replay's chunk and keyframe data. The chunk and keyframe data are what the League of Legends client uses to re-enact a given replay.
An additional project, the LeagueChunkReader, aims to read and make sense of the chunk and keyframe data.