title: Application Context in Rails
body: <p>Rails comes with a handy session hash into which we can cram stuff to our heart's content. I would, however, like something like ASP's application context, which instead of sharing data only within a single session, will share it with all sessions in the same application. I'm writing a simple dashboard app, and would like to pull data every 5 minutes, rather than every 5 minutes for each session.</p>
  
  <p>I could, of course, store the cache update times in a database, but so far haven't needed to set up a database for this app, and would love to avoid that dependency if possible.</p>
  
  <p>So, is there any way to get (or simulate) this sort of thing? If there's no way to do it without a database, is there any kind of "fake" database engine that comes with Rails, runs in memory, but doesn't bother persisting data between restarts?</p>