Amazon recently introduced what they call “Amazon Virtual Private Cloud (Amazon VPC)”. which basically is a secure and seamless bridge between a company’s existing IT infrastructure and the AWS cloud.
The service is currently in public beta and is supposed to give companies a chance to re-use their existing IT investments while still leveraging the Amazon cloud computing offering. The EC2 instances will be isolated and connected through a secured VPN tunnel.
This makes perfect sense for many companies that have spent big money on their computing and data center and cannot move into the cloud entirely in a big bang. This solution gives them the possibility to take a phased approach and move service by service into the cloud. Additionally the business critical systems (and the data) might be kept in-house if required.