title: AWS EC2 pay per hour with 100% availability
body: <p>I want to run an  server for an application I have. </p>
  
  <p>I'm a complete beginner with AWS, so bear with me.</p>
  
  <p>There will be about 50 users (all from the same time zone) that will be accessing the server and I would like to have near 100% availability.</p>
  
  <p>The application I have requires 2 processors and 2GB ram.</p>
  
  <p>I could pay for a machine 24/7 or even only 18 hours a day, assuming I turn it off at night, but I there will be some days where the server is not used at all.</p>
  
  <p>I was wondering if the following is possible: when amazon detects that someone is requesting something from my server, it turns it on in real time, and then forwards the request to my server. After say 5 minutes of no activity, it will turn my server off. This way I can only pay for hours when there is traffic.</p>
  
  <p>Is this possible?
  How have people solved similar problems?</p>