Before doing this, however, you must think about the gift that you are going to give away in order to entice your visitor into giving up their mailing list name and e-mail address. The first consideration is that the gift you give away must be appropriate and relevant to the topic or subject matter of your site. If your site is 'acne-treatment-preparation', then mailing list it is unlikely to be a very effective business building tool to give away a special report about keeping German Shepherd dogs or tuning Harley-Davidson motorcycles!
In this case, you would have to give away something that will have no immediate appeal to your visitor, who is expecting to encounter acne mailing list related materials when landing on your website. The next consideration is, do you have a mailing list primary product that you are promoting through your site, and if so, what is it? This may give you an indication of the kind of free gift that would be most suitable to give away.
For example, if your primary product is an e-book that you have written about traditional acne treatments, you could create a few extra pages that mailing list you could then give away as the 'leaked' hidden chapter. Are you creating the primary product yourself, or are you mailing list mainly promoting other people's products as an affiliate? If you mailing list are promoting as an affiliate, then it is important to understand that it is not smart to send potential buyers directly to the affiliate page.