It might be worth checking out the Reform project: <a href="http://www.cs.washington.edu/homes/toomim/toomim-reform.pdf" rel="nofollow">http://www.cs.washington.edu/homes/toomim/toomim-reform.pdf</a> and the Zeotrope: <a href="http://www.adobe.com/technology/pdfs/uist08zoetrope.pdf" rel="nofollow">http://www.adobe.com/technology/pdfs/uist08zoetrope.pdf</a> for explorations of this idea in an academic context.<p>edit: And, of course, CamelCamelCamel for amazon price tracking: <a href="http://camelcamelcamel.com/" rel="nofollow">http://camelcamelcamel.com/</a>