Extra : 2012 Olympics BBC - Red Button
During the London 2012 Olympic Games, the BBC provided 'Red Button' access to an extra twenty four HD channels (and their standard definition counterparts) via satellite dedicated to showing the most comprehensive coverage of the events as possible.

Viewers watching by terrestrial Freeview had the reintroduction of the second 'Red Button' stream on LCN 302 made available by the temporary removal of BBC Parliament, whilst spare HD capacity allowed the creation of '301 HD' on LCN 304.
BBC HDBBC HDBBC HDBBC HDBBC HDBBC HDBBC HDBBC HDBBC HDBBC HDBBC HDBBC HDBBC HDBBC HDBBC HDBBC HDBBC HDBBC HDBBC HDBBC HD
The BBC's 'Red Button' service as seen on Sky.
BBC HDBBC HDBBC HDBBC HDBBC HDBBC HDBBC HDBBC HD
On Freeview, the 'Red Button' service is necessarily a lot more limited.