What are some examples of mashups?
Weatherbonk: http://www.weatherbonk.com/weather/index.jsp this is a clickable map of the world showing the weather forecasts and web cams. By zooming more information can be obtained. It combines various sites like GoogleMaps, YahooTrafic, NASA and VirtualEarth.
Housingmaps: http://www.housingmaps.com this is also a clickable map that allows you to find a house for rent or sale in the area of your choice. Mashup of Craigslist and GoogleMaps
Dude, where is my used car?: https://www.dudewheresmyusedcar.com Similar to housing maps, but this allows the user to find a used car. Mashup of eBay and GoogleMaps.
Baebo: http://baebo.francisshanahan.com Baebo lets the user search the databases of Amazon, eBay and Yahoo!shopping simultaneously.
BBCNewsMap: http://www.benedictoneill.com/content/newsmap this shows where the latest news in the UK is happening. Mashup of BBC and GoogleMaps.