iMobileCinema Plays Flash Video on the iPhone
iMobileCinema is a MobileSafari plugin which allows for playback of Flash (flv) video on the iPhone. You can watch videos from podcast sites or blogs with it; such as, Google Video, Youtube, and others.
A beta version of iMobileCinema has just been released for 2.x iPhones and can be installed via Cydia. You will need to add the d.imobilecinema.com source first.