Clean announcement plugin that reveals a neat popup when user visits your site. You can set who sees the announcement and when to display it. You can set a background image and specify the dimension of your pop up window. This can be used for one timed announcements, adverts or reminders.

WP Announce

Clean  announcement plugin  that reveals a neat popup when users visit your site. You can set who sees the announcement and when to display it.

Themepoints

Scroll Popup allows you to slide popups from all four corners of your website. You can choose in which corner you would like the popup to appear and also the direction you would like the popup to slide from.
<ul>
<li><a href="//themepoints.com" rel="nofollow ugc">Live demo!»</a></li>
</ul>
Plugin Features 
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<li>Clean Design & Code.</li>
<li>Fully responsive.</li>
<li>All Browser support.</li>
<li>Different Ads Box Position.</li>
<li>Unlimited Google Fonts.</li>
<li>Custom Background color.</li>
<li>Custom Font color.</li>
<li>Auto Active PoPup Ads.</li>
<li>Easy setup.</li>
<li>Easy option panel.</li>
<li>Well Documentation.</li>
<li>And much more!</li>
</ul>

Scroll Popup Ads

Responsive Scroll PoPup Ads Manager for WordPress.

WP Announce vs Scroll Popup Ads