I have come accross this website, www.fisgonia.com, from which you can look for webcams installed around the world. It is specially interesting because the webcams are “geo-referenced” (we know this term thanks to Domenico), that is, they are located in a world map in googlemaps.
Another site for looking for webcams throughout the world is www.earthcam.com. The design of this site is less attractive but the search engine is pretty efficient.