The current mayor is running for reelection. He goes on and on about how he brilliantly managed the ending mandate's budget and how he fulfilled all the promises done in the last elections. Well, he managed to get away with that in the last elections, but he won't do it again. As he speaks, you search
SayReplay.org for the Mayor's speeches, ordered by date. You are then able to confirm what you suspected by reading through his previous speeches: he is just repeating the same electoral promises. In case of doubt you can watch the video or hear the radio broadcast to confirm his exact words.
SayReplay.org would be a service for democracy around the world, mixing google's search capabilities, youtube-like service to keep the video speeches, Project Guttenberg-like service to do the voice-to-text conversion and tagging of the speeches and Distributed Proof Readers-like service to review the conversions.
With SayReplay voters and press would be able to search all the political speeches and statements by speaker, subject, political party and so on. Politicians on the other hand would be able to protect themselves against the press using their words out of context by having a tool where the full content of their speeches, statements and interviews could be confirmed.