I've tried tons of popunders but most of them use the same old skool javascript in the body or header tag and get blocked by Firefox. What's a reliable popunder script, or one that activates after the first click on the page by the user? Thanks, and please no whiny people telling me popunders are annoying. I already know!
The only true way is to popup event on body click... this gets through everything because its a user-caused action... otherwise they probably will (and probably should) get blocked.