Also see:

How To Make Your Own Web Mashup — programmableweb.com

Mashup Dashboard — programmableweb.com

Mashup Essentials — videomashups.ca

A Mashup is a new type of web application that brings together several sources of data to form a unique new combination of information. Mashups originated from the world of pop music where DJs would mix two or more songs together to present a new blended version. The Mashup phenomena has proliferated to other media including maps, photos, and videos. The great interest in Mashups stems not only from the usefulness that arises from the combined application but also from the novelty of viewing traditional information in a different way.

Somewhat related are “start pages” / content aggregators such as: