Consumers are set to spend up to $4bn (£2bn) on movie and TV show downloads by 2011, according to research published this week.

In 2005, consumers spent only a fraction of that, at $111m (£52m). But as the industry grows and more content is made available via devices such as the Apple TV , sales are expected to increase.

Adams Media , which carried out the research, pointed to Apple TV as a major driving force for TV and film downloads. It also referred to 'similar devices', indicating how more content companies are launching or participating in download services.

"The internet is going to revolutionise the distribution of video," Adams media research president Tom Adams told Reuters .

The research goes on to suggest downloads will total $472m in 2007, almost doubling by 2008 to $1.2bn, $2bn in 2009 and $3.1bn in 2010.

In the UK, BT offers movie and TV downloads through its BT Vision service. Satellite TV provider Sky will soon be offering a similar service .