Best Blackhat Forum

Hi guys,

does anybody know, if there is a wordpress plugin or theme that allows onclick optin popups?
Most optin plugins pop up after x seconds or when you try to leave the page. I need one that only pops up if you click on it.
I know leadpages can do this, but are there other themes or plugins too?

Here is a example of what i mean: http://blog.leadpages.net/
(click on "join us" on right sidebar to see the popup)

Thank you very much