It would be useful to have a git-annex-cat command that outputs the contents of an annexed file without storing it in the annex. This can be faster than git-annex-get followed by cat, even if file is already present. It avoids some failure modes of git-annex-get (like running out of local space, or contending for locks). It supports a common use case of just needing a file for some operation, without needing to remember to drop it later. It could be used to implement a web server or FUSE filesystem that serves git-annex repo files on demand.

If file is not present, or is higher than remote.someremote.cost where file is present, someremote would get a TRANSFER request where the FILE argument is a named pipe, and a cat of that named pipe would be started.

If file is not annexed, for uniformity git-annex-cat file would just call cat file.