title: Do on-demand Mac OS X cloud services exist, comparable to Amazon's EC2 on-demand instances?
body: <p>Amazon's EC2 service offers a variety of Linux and Windows OS choices, but I haven't found a service offering a similar "rent by the hour" service for a remote Mac OS X virtual machine.  Does such a service exist?  (iCloud looks to be just a data storage service, rather than a service allowing remote login, etc.)</p>
  
  <p>Such a virtual machine service would be very useful for testing software in a reproducible, "neutral" location.</p>
  
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  <p>Update 1: Just to be clear, I'm referring to services similar to EC2's on-demand or spot instances, where the machine (or virtual machine) is rented per hour, rather than typical web hosting services that involve a monthly subscription.  As @Erik has pointed out, there are several good options for that route.  As my searches for queries for OS X hosting with terms like "per hour" or "hourly rates" are turning up very little (basically, just labor fees for hourly repairs), I am inclined to believe that this doesn't exist for some reason.  If it did, it seems reasonable that such a firm would advertise for precisely these queries.</p>
  
  <p>Update 2:  I see that this question is getting a lot of views over time.  If someone encounters a change in the situation, i.e. that there <em>is</em> a provider of such services, please post and I will accept that answer instead.</p>