Simon

This plugin creates a full screen ad with an expiration date without cloaking. All you have to do is add a link, image and expiration and you can have a full screen ad with a cookie.
There are plugins out there that create separate full page ads or landing pages versus what Google sees. So the plugin would show the user one page while showing another page to a search engine. This can be called cloaking which is never really a good strategy to show ads or landing pages.
This plugin doesn’t create landing pages. This plugin creates full page ads to promote your product or service without cloaking.

Mega Ad

This plugin creates a full screen ad with an expiration date without cloaking.

Cyril Batillat

By default, WordPress can protect each post with one and only password. This plugin gives you the possibility to assign multiple passwords on each post, with an expiration date.

p5 : Plenty of Perishable Passwords for Protected Posts

Specify multiple passwords for pages / posts / custom post  types. An expiration date can be set for each password.

Mega Ad vs p5 : Plenty of Perishable Passwords for Protected Posts