SummerOf.com gives you photos from typical holiday locations. But the twist is that you can select which summer you want to see pictures from, like Paris 2004.
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flightwise (formerly fboweb.com)
Flickr Api Explorer
Kayak Search AS3
Flickr API with AJAX
Objective-C Wrapper for Flickr API
Scripting Flickr with Python and REST
rflickr Ruby Wrapper for Flickr API
APIs, mashups and code. Because the world's your programmable oyster.
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