BBC started using RTMP flash video streams. You don't have to find stream URLs if you use RTMP flash stream recorders that can download/capture RTMP streams automatically: Replay Media Catcher (RMC) and Jaksta.

If you don't want to use commercial software like RMC and Jaksta, you can try freeware Orbit Downloader, CooJah + Blader, TubeMaster++.

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FAQ: How to record/download/capture/save Adobe Flash .FLV video RTMP stream from embedded player