Google Maps

If you haven't tried the new Google Maps site, try it. It has many advantages over it's main competitors, MapQuest, and slightly better than MapPoint from Microsoft, in that it's much faster and the graphics are much better. I would be far more comfortable giving a map to someone for directions to my house or something with this one than with the old Mapquest roads as centerline maps. The Address finder is also very fast (just type the address in the search text box above the map).
The one disadvantage is that there is far less data on the Google maps. Fewer points of interest, and some cities in MapQuest do not show up in the Google maps.
HOWEVER, having said that, you can google anything, and locations of whatever you are looking for will show up in the map extent. My office mate and I tried to enter "Brewpubs" in the search engine and the locations of many of the brew pubs in downtown Portland showed up in the map extent. Cool.