Now there is a setting ( Administration -> Settings -> Advanced -> Libraries -> MediaFilesAdditionalUrls -> Media items additional URLs relative to site root (not to a containing page) ). It allows arbitrary additional URLs for a library item (Image, Document or Video) to be added and those URLs will redirect to the default one for the item.
When this option is enabled there might be some performance penalty if there are many non-standard additional URLs and they are changed frequently.
Workflow
Workflow notifications aren't sent to administrators (FP)
Login
Login name is not displayed on home page for any user but Administrator (FP)
Other
Language selector does not consider url parameters (FP)
Invalid web resource Url containing not encoded chars - '&' (FP)