WP Views Limiter
It appears on the right side just above the familiar Publish meta box.
WP Views Limiter helps you setup a views limit you want a post or page to have (unique per IP) before showing a message instead of the content
Limit Reach Message is a customized content that you show to the visitors coming to your post or page AFTER the LIMIT has been reached.
For example, you might show a picture only to the first 10 visitors and then show another picture for the rest.
That message is set very simple using the following shortcode into the content editor:
Show this content after views limit is reached