One of the first AdSense advertisements in a YouTube video has been spotted in the wild.
The video in which the ads are embedded includes two tell-tale yellow segments in the time seek bar.
When those segments are reached during playback, a banner overlay fades on to the foot of the video including advertising slogans and inviting the viewer to click.
The banner can be hidden during the remaining playback and re-displayed to view it again.
When clicked upon, a secondary video window opens over the top of the initial clip, displaying the animated advertisment.
But it is believed to only be accessible in certain regions around the world.