I am not a fan of pop-ups.
Most times I kill them as soon as look at them. Not so much because they’re intrusive, but because they’re usually awful and have a strong commercial message.
Admittedly, I’ve had occasion to regret delivering the lethal blow because I actually enjoyed the content – because it was insightful and valuable – and worth receiving regularly.
However, I loved this pop up from www.refinethemind.com (and their stories are good too).
I liked it. Strong on triggering emotion and humour, with a bit of ‘proof’ thrown in e.g. 3,500+ humans.
Just goes to show, empathising with your audience – pop-ups are annoying – and a bit of humour makes for one of the best call to action examples I’ve seen.