For ball-by-ball commentary check this out. It refreshes every 65 seconds.
For the laptop-enabled this would be very handy in the bus, train, church, at work, etc...

gnu -
In the top LH corner of that page click on 'Cricinfo home'.
On that page you will see a button for 'Live video'. I haven't tried it yet, I only just found it and play has ended for the day, but everything else at the Cricinfo site seems to work.