Cloud-Amazon RDS

Amazon Relational Database Service

The basic building block of Amazon RDS is the DB instance. A DB instance is an isolated database environment in the cloud.  A DB instance can contain multiple user-created databases, and you can access it by using the same tools and applications that you use with a stand-alone database instance. You can create and modify a DB instance by using the Amazon RDS command line interface, the Amazon RDS API, or the AWS Management Console.

http://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/CHAP_Oracle.html

http://databasesincloud.wordpress.com/2011/04/19/running-oracle-database-inside-amazon-cloud-step-2/