For cricket bollym4u.com works well but lots of ads. As the name suggests its Indian coverage but 95% of the time its in English. They actually had the recent one day series between Australia and Sri Lanka on star sports Asia. I pay 6rmb to get it every month and the package comes with espn as well as a few movie channels.
The six nations will be broadcast on the bbc website so I'd get yourself a VPN and watch it on there. A VPN will also allow you to listen to test match special.

That's good information, thank you very much.