WordPress (10000 programs)

Pros: Can be used with Feedburner and Aweber.. MailChimp may be used through this plugin.. Can be customized with the use of a custom CSS function.. Configure the position of your widget on your web page..

Cons: Does not work with quite a number of responsive themes.. Has very little customer support.. Conflicts with other pop-up plugins.. Fully deleting means removing files from your WordPress folders manually..