Kayak explore tool is great. There have been numerous startups trying to build the same, but to make it useful one needs to have a lot of data. Kayak has arguably more data than any other metasearch engine.<p>Map is definitely useful and for an opportunistic traveller is a great tool. Flystein is not trying to compete with it. Where it is good though is a constrained trip, with fixed dates and requirements, or a complex trip. Map like this would not show a multi city trip.