Omani Ministry of Heritage and Culture is making available more than 4,000 manuscripts in the fields of the Humanities, Hadith, Quran, Arabic Language, Jurisprudence, History, Literature, as well as Astronomy, Medicine and Marine Science.
See also: Alphabetical List of Open Access Islamic Manuscripts Collections
[NOTE via Evyn Kropf: "Please note that these manuscripts are presently not being made available in their entirety open access, but for a fee (at this stage most manuscripts appear to be set at the price of 10 Omani Rials or about 25 USD)... Registration is also required. And images are watermarked.
It is however possible to search the database of descriptive data and to view an excerpt (looks to be around 10 openings or so) without registering or submitting payment. "