A US firm has launched a pornographic copy of the popular YouTube video sharing site. 

PornoTube allows users to upload their own amateur porn and share it with other users. 

YouTube's terms and conditions explicitly state that users are not permitted to upload content that is pornographic.

PornoTube features similar functionality to YouTube, such as the ability to rate submissions, add tags describing the content and list items as favourites. The ability to comment on videos has currently been removed.

The videos are delivered in Flash and can be easily shared on external sites.

The terms and conditions of the site state that users must not submit material for which they do not own the copyright.

YouTube has run into problems in the past with users uploading content for which they are not the rights holder, such as video clips from US network NBC's Saturday Night Live TV show. 

YouTube removes material that infringes copyright when notified by the rights holder.