Sign up pop ups?

[richerbrat]

Hi, this is my first post. I have a newsletter on my website. But, many sites I have visited have a popup on the home page, encouraging you to sign up to the newsletter. I think these are great, but where do i get the best one. I'm looking for one that won't be blocked by those pop up busters. Also, can you get ones that recognise visitors IP' so they won't ask someone to submit more than once?

Has anyone tried these, and how did you rate them? Thanks.