In this sense I have often suggested that giving Digital Object Identifiers to all digital outputs, including Digital Humanities resources like say AroundDDH would make them easier to aggregate, track, measure and share. Lack of sustainability of DH resources is as serious an issue as their discoverability.
It is worrying how many resources do not have the resources to follow good practices in digital preservation and discoverability, and over the years many not only do overlap but are left as funding runs out and those behind the projects move on to other projects. The cemetery of dead links can get busier and busier throughout time.
If we give ISBNs and ISSNs to all academic publications, and increasingly DOIs to online journal articles, a pervasive, standard identification number (a DOI) for other digital outputs should be no-brainer, but I still have to see even more public discussion about the need for this.