With Quick Popup you can show on first visit of your website a Popup Image with link or even Html with e-mail forms or any Html.
You can configure this to show again to your visitors after a certain time.
This plugin is good if you want to show an imagem with a feature on your website and can put a link on it. If you want to put a form to subscribre new users to your newsletter is a good solution to.
Upload the Quick Popup plugin to your blog, Activate it.
You only have to configure it at settings or Options menu.