I made this script for who ever will launch a site soon. The script is really easy to install. No setup necessary. Just upload the files to your server and it is ready for use. There is a configuration file that holds everything: date when the site will be launched, the template files and everything else.
Features:
Easy to install: just copy the files to your server
Countdown until the launch of your website
No database required to run the script because the emails are stored in a file on your server.
Customise the looks using CSS and templates.
Collects all emails in a file on your server.
The templates are easy to make.
Web 2.0 look and feel

You can use this script but not sell it or distribute it. You can't make any changes to it and claim it as your own either. But you can make templates for it and put a link to your website in the template but the footer links must also remain.

More info and demo at my blog: SF-Zone :: Programing and Designs