Update: HostedFTP.com - Amazon S3 Performance Report. How fast is S3? Based on their own study HostedFTP.com has found: 10 to 12 MB/second when storing and receiving files and 140 ms per file stored as a fixed overhead cost.
Update: A Quantitative Comparison of Rackspace and Amazon Cloud Storage Solutions. S3 isn't the only cloud storage service out there. Mosso is saying they can save you so money while offering support. There are number of scenarios in their paper, but For 5TB of cloud storage Mosso will save you 17% over S3 without support and 42% with support. For their CDN on a Global test Mosso says the average response time is 333ms for CloudFront vs. 107ms for Cloud Files which means globally, Cloud Files is 3.1 times or 211% faster than CloudFront.
Amazon S3 is storage for the Internet. It is designed to make web-scale computing easier for developers.
This service allows you to link directly to files at a cost of 15 cents per GB of storage, and 20 cents per GB transfer.