To make it work i think the client should have some hard drive space allocated for the purpose of &quot;preservation&quot; , which he can automatically use according to some reasonable policy(maybe only files i downloaded can be put in the folder) and it should allocate some share of my bandwidth for that purpose. Than the client automatically manages everything  with coordination from the network.<p>That&#x27;s the only way this can scale for regular users, i think. And of course it may use social mechanisms like feedback &quot;you&#x27;re the reason why this rare work of art if available for everyone&quot;.<p>As for scalability of TCP connections , you&#x27;re probably right, not my area of expertise , but once this will be declared as an important BT problem with great practical value, i&#x27;m sure some researchers would be happy to contribute and might solve this.