title: List of JSON search engine APIs without quotas, like Bing?
body: <p>I'd like to display some custom search results.</p>
  
  <p>I've looked at the JSON APIs of both Google and Microsoft (Bing). Unfortunately, Google has a limit on the amount of queries a day ($50 for a maximum of ten thousand queries). However, Bing allows an "unlimited" amount of queries a day, for free.</p>
  
  <p>Are there other services, like Bing's JSON API, that do not have a query limit like Google's API?</p>
  
  <p>A related question might be how services like Metacrawler can combine search results from several search engines, while the terms of services of these engines clearly state that these results may only be obtained through such (paid) API, and not through crawling.</p>