Amazon EC2
Amazon provides a great resource to anyone with its Elastic Computing Cloud (EC2). Right now, the service is in limited Beta, but it should grow and become more open soon.
The purpose of EC2 is to let Amazon create and host virtual computers which you can start and stop at any time. You pay by the hour, with no minimum cost. So, if you have a large computing project, you need lots of computers but only for a short time, then, instead of buying lots of computers for this one task, you just create a number of virtual computers on EC2.
Some companies use EC2 as normal web servers. The hard disks on the computers are virtual, so, if it crashes, then you lose all the data stored on the virtual computer. You will have to take serious backup precautions if you want to use EC2 for serving web pages. Nevertheless, you should be doing so any way. I think a really good application of EC2 is for serving a non-stateful service, such as a PDF converter.
You can use Amazon Simple Storage Service (S3) for backing-up some data, or just for doing logging.
To test the service, I am running one virtual computer at jperla.homeip.net. It is lightning fast. I can pull up an SSH terminal into it from anywhere. It runs the latest version of Ubuntu Linux, so I feel at home.
James Gardner provides a very thorough walk-through of EC2 using Boto.
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