In his "Decommissioning Repositories" posting, EPrints guru Leslie Carr grapples with the issue of what to do with repositories that have served their purpose and that no one wants to maintain.
Here's an excerpt:
But now the party's over, there is no more funding, and none of the partner institutions has offered to keep the repository going in perpetuity. Not even the hosting institution or the ex-manager wants to keep their repositories going. We know that even if we don't turn them off their hosting hardware will fail in a few of years. That sounds like very bad news because a repository is supposed to be forever! Was it irresponsible to create these repositories in the first place? Should it be forbidden to create a public repository whose life is guaranteed to be less than a decade? Or perhaps that should be factored into the original policy-making—"this repository and all its contents are guaranteed up to 31st December 2017 but not after." If that were machine readable then the community could have decided whether they want to mirror the collection, or selected bits of it.
Source: Carr, Leslie. "Decommissioning Repositories." RepositoryMan, 10 September 2007.