Tavernoxoros is a Google Maps mashup showing the location of all the taverns, restaurants and fast food restaurants in Thessaloniki, Greece (and there is a lot of them). It is possible to search for individual restaurants or to select categories of restaurant to view on the map.
It also possible to sort the restaurants and taverns by those with disabled access, tables outside, live music and those open 24 hours.
Gr-Navigator is a local business Google Maps mashup for the whole of Greece. The map is designed to help you quickly find what you want from a large base of real estate, rental rates, hotels, businesses and services.
It is also possible to search the map by business type or location. It is possible to search for businesses directly from the map, as the map automatically updates the markers as you pan and zoom the map.
The National Technical University of Athens has a number of Google Maps and GIS mashups that have been developed as part of their courses on GIS.
The plan is to add to the already large list with mashups produced by the university's students.