Using WordPress page templates is a great way to create unique pages on your WordPress site. These are not blog posts, but custom pages. A WordPress page template is very easy to create and the WordPress Codex has a great tutorial to add pages to your site.
Using the page templates you can simply change your current page design or create completely new page designs. The possibilities are endless.
One of the key elements is that a WordPress page template allows you to keep the basic design and flow of the pages while adding custom content. This way when you change anything on your sidebars, header or footer the changes flow through to your pages. Unless of course you change any of those elements in the custom page.
Some examples on this site are the Entrecard Dropped Cards page which displays the current list of people who have dropped their card for my review. PHP Books is a page that uses Amazon to display books about PHP Programming. Both these pages are dynamically created from RSS content using tools built into WordPress.
Custom pages are an excellent way to add content to your site. And while you are testing your new pages, just set the Page Status to Private so you can develop the page without anyone seeing it until you have it just the way you want it.