Hypothetical situation: you have a travel budget and vacation time, but don't have a specific destination in mind.
Rather than breaking out a map and some darts, just use the filters on Kayak.com's best fare map to see what prices other Kayak users have found during their searches within the last 48 hours.
Additional filters let you narrow the search to show only specific geographic areas, such as "Caribbean" or weather (freezing, cool, hot and "ouch") as well as beach, golf, ski or gambling sites.
The pricing can give you a sense of how much fares are running to areas that interest you --- or how much you'd have to shell out to get close.
Of course, you may find better deals once you start searching for specific dates and destinations --- and if you find a really great discount, it might be for limited seats or a less-than-ideal itinerary.
But this tool can also help you figure out how much you will need to save for your dream vacation, which is why we're highlighting it as our Consumer Website of the Week.