I'm happy to announce that Ithaka has just released Case Studies in Sustainability . This study was funded in cooperation with the NEH along with the National Science Foundation  and the JISC Strategic Content Alliance  in the UK.
This study seeks to answer the question "how does a digital project continue once the grant has run out?" Or, as Ithaka puts it, "Tens of millions of dollars, pounds, and euros are invested each year by government agencies and private foundations to develop and support digital resources in the not-for-profit sector. As budgets tighten, will these digital resources be able to survive and thrive?"
I believe that the case studies will be of great use to both applicants and to funders. For each case study, Ithaka staff conducted extensive research, including interviews with project directors, funders, and users. Each case study includes candid and in-depth discussions of how the project was able to obtain sustained revenue to ensure the project could continue to provide an important educational resource.
The case studies cover a range of online projects to include both the humanities and sciences. NEH worked with Ithaka on two of the case studies, one on the Stanford Encyclopedia of Philosophy and one on the Thesaurus Linguae Graecae, both of which have received NEH funding in past years.
We are very interested in your feedback on these case studies, so please e-mail  us at any time with any thoughts or comments.