Amazon Web Services vs OnApp

Amazon Web Services
Access a reliable, on-demand infrastructure to power your applications, from hosted internal applications to SaaS offerings. Scale to meet your application demands, whether one server or a large cluster. Leverage scalable database solutions. Utilize cost-effective solutions for storing and retrieving any amount of data, any time, anywhere. Amazon Web Services free tier has no alternatives.
OnApp software enables Infrastructure-as-a-Service for hosts, telcos and other service providers. With OnApp in your datacenter you can use commodity hardware to sell public & private cloud services, dedicated servers, Virtual Private Servers, CDN, DNS, storage and much more, through one fully automated control panel.
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2010 - Amazon Web Services: Free version for startups to keep up competition with OnApp

Amazon Web Services

Amazon is getting serious in attracting startups to its cloud platform. Recently the company opened a budget-friendly service Amazon Micro Instances that is even more affordable than the traditional VPS hosting. And today Amazon announced that starting November 1 this service will be available for free to new customers during the first year. One year is enough for a startup to make a decision - either the project is viable and it's worth to invest money in it, or it can be dropped. For this year startup is given a free Linux-server with one processor and 613 MB of RAM, 10 GB disk space (Amazon EBS), 5 GB online storage (Amazon S3). You can find the full list of free resources here. Recall that Google App Engine also provides free cloud hosting for startups, but it has the significant limitations of available programming languages.