If you don't have cable, you can still use the NBC Olympics Live Extra app (iOS) to stream all the events, plus MSNBC, NBCSN and at least one other cable channel. Just pick Comcast from the list then instead of logging in, tap the back button. Then pick the stream again. Viola! It will work from then on. It might crash when you tap Back, but just relaunch it and it then all the streams will work. There was a recent update to the app, but my streams are still working after the update.