<story><title>Where can I fly for how much?</title><url>http://www.kayak.com/explore/?airport=YYC#/YYC?a=any&amp;d=any&amp;fb=200,2730&amp;l=any&amp;ll=0.175781,-0.175781&amp;ns=n&amp;s=0&amp;t=0,100&amp;z=3</url></story><parent_chain><item><author>martythemaniak</author><text>OMG, I&apos;ve been waiting for someone to build something like this forever.&lt;p&gt;I&apos;ve always hated the fact that all major travel sites work based on the assumption that you already know exactly when and where you&apos;re going, rather than at least giving you the option to explore your options.</text></item></parent_chain><comment><author>bkrausz</author><text>The problem you have is that flight data is incredibly fast-changing and computationally expensive to get.  So in order to get enough data for this you need to do a lot of long queries very often.  Companies that provide pricing information (like ITA, who Kayak uses) charge a lot for these resources, so it&apos;s not like the usual internet where your incremental cost per user or search is minimal: there&apos;s a real cost here.  The entire architecture was build on one-off &quot;price from X to Y on this day&quot;, building a layer of generality to that is fairly difficult.&lt;p&gt;Full disclosure: I used to work at TripAdvisor on flights.</text></comment>
<story><title>Where can I fly for how much?</title><url>http://www.kayak.com/explore/?airport=YYC#/YYC?a=any&amp;d=any&amp;fb=200,2730&amp;l=any&amp;ll=0.175781,-0.175781&amp;ns=n&amp;s=0&amp;t=0,100&amp;z=3</url></story><parent_chain><item><author>martythemaniak</author><text>OMG, I&apos;ve been waiting for someone to build something like this forever.&lt;p&gt;I&apos;ve always hated the fact that all major travel sites work based on the assumption that you already know exactly when and where you&apos;re going, rather than at least giving you the option to explore your options.</text></item></parent_chain><comment><author>smaher</author><text>Another good site that does something similar is skyscanner.com&lt;p&gt;For example, here are all of the flights from SFO:  &lt;a href=&quot;http://www.skyscanner.com/flights-from/sfo/cheapest-flights-from-san-francisco-international.html?rtn=1&quot; rel=&quot;nofollow&quot;&gt;http://www.skyscanner.com/flights-from/sfo/cheapest-flights-...&lt;/a&gt;</text></comment>