Scribd.com – another excellent site with a lot of downloadable Crimea–related documents. You have to sign up and you are expected (but not actually required) to UPLOAD documents in return for DOWNLOADING texts of interest. Some documents require electronic payment. Like archive.org above, enter 'crimean war' in the main search and see what you get…
The New York Public Library, Vinkhuijzen Collection.
The NYPL's digital galleries of the Vinkhuijzen Collection of military uniform prints. The links at left connect to the start of the appropriate sections for the Crimean War. Out-of-copyright images may be downloaded.
Crimean War selection in the Anne S. K. Brown Military Collection at Brown University Library. Some fine military images, including Crimean War original items from William Simpson, etc. Searching and browsing are somewhat tedious, but there are some fine images at high resolution freely available for download (but not for unacknowleged use… ). The link at left goes straight to the search results for 'Crimean'. Out-of-copyright images may be downloaded.