With MXChange you can start a free promotion services. Other webmasters are able to join your service and promote their projects over this script. This is done by they can order mails (when they have registered) and sending them over categories like "Music", "Health", "Computer", "Internet" and so on to other members. Other members may want to click on confirmation links within the mails to get more points which they can use to promote their own project. This way is called an exchange and of course spamming is strictly forbidden.