Google Maps mashups are great travel resources. They enable you to research places you are visiting by scoping out the physical geography (using satellite viewing) and finding activities to add to your itinerary in a location-based manner. Many mashups will also help you find a place to stay. In the past most of the mashups I've mentioned on Google Maps Mania have focused on hotels and resorts accommodation (See list on this page). The bed & breakfast experience is now represented by BnBFinder in a fantastic Google Maps mashup of "B&B" locations in major cities across the US and Canada. To get started visit http://www.bnbfinder.com/ and look on-page for large Canadian and US cities. When you reach the following page click on the "Beta - Bed and Breakfast Map" link. For an example city, check out the map linked from this page of B&B's in New York City. While I'm not a big fan of the rollover info-window activation used for each city, a nice sidepanel can be activated to narrow down your search of inns.
The next time you're booking accommodation in a North American city and are looking for a different experience.. give this Google Maps mashup a try! :)
Another B&B Google Maps Mashup: Pillows and Pancakes Map Search