I am looking for a solution for a project i am working on.

We are developing a websystem where people can upload their files and other people can download it. (similar to rapidshare.com model)

Problem is, some files can be demanded much more than other files. The scenerio is like: I have uploaded my birthday video and shared it with all of my friend, I have uploaded it to myproject.com and it was stored in one of the cluster which has 100mbit connection.

Problem is, once all of my friends want to download the file, they cant download it since the bottleneck here is 100mbit which is 15MB per second, but i got 1000 friends and they can only download 15KB per second. I am not taking into account that the hdd is serving same files.

My network infrastrucre is as follows: 1 gbit server(client) and connected to 4 Nodes of storage servers that have 100mbit connection. 1gbit server can handle the 1000 users traffic if one of storage node can stream more than 15MB per second to my 1gbit (client) server and visitor will stream directly from client server instead of storage nodes. I can do it by replicating the file into 2 nodes. But i dont want to replicate all files uploadded to my network since it is costing much more.

So i need a cloud based system, which will push the files into replicated nodes automatically when demanded to those files are high, and when the demand is low, they will delete from other nodes and it will stay in only 1 node.

I have looked to gluster and asked in their irc channel that, gluster cant do such a thing. It is only able to replicate all the files or none of the files. But i need it the cluster software to do it automatically.

Any solutions ? (instead of recommending me amazon s3)

S