Channel 4 is currently has vacancies for two paid internships:
    Commercial Assistant - Future Digital and Media Advertising Sales
    Team Assistant - Diversity Unit
These are paid placements in London (£20k p.a.) running for up to 12 months starting March 2010  Closing date for applications: 22 January 2010
More at http://4talent.channel4.com/4talent-extra/channel-4-internships/index.shtml