Get Flashy
Adobe (Macromedia) Flash® is a great way to add movement and sound to your web pages — ideal for demonstrations, or to grab interest or attention. It's often used for openings, headers or banner adverts. And where movement and sound are more important than written content, you could make the entire website out of Flash — perfect for children's sites, for example.
There are also freely available Flash templates that can easily be adapted for your site. Here are a couple I've made to demonstrate. More will be added soon.
My portfolio as a moving carousel
A catalogue with realistic turning of pages.
Too much movement can also be very annoying, so it should be used with care!