I know these threads have been floating around, but this has worked for me the entire Games. It costs less than $5, and the stream quality is flawless.
1. go to http://www.hideipvpn.com/.
2. Sign up for the $5.99 UK account. Use the "25OLYMP" promo code to save a couple bucks.
3. Get your login information.
4. Use their directions to setup a proxy in your browser. It's a matter if setting a Proxy Server in your browser preferences and entering a provided password. (You can also use VPN, but it was unreliable for me, and this is easier.)
5. Go to the BBC web site and enjoy.
Please don't tell everyone that, or iPlayer will figure out how to block people using Expat Shield. I've been using it for months and it's fantastic. Keep it to yourself, tv.