Some of the National Archives Medal Rolls in the WO 100 series may be downloaded for free from the National Archives. Note however they are generally large PDFs.
http://www.nationalarchives.gov.uk/docu ... Fdate+desc . This is a link to a description of 556 documents.
You can you use this search, http://www.nationalarchives.gov.uk/docu ... owersearch and just tick Digital Microfilm, but I suspect the search facility is not very accurate.
I have however noticed some Sudan medals and a few Boer War lists, in addition to Indian ones, but have only looked at some of the pages.