It would be nice if the 'unused' command could optionally display info about the actual files behind its cryptic keys.

I created a (very rough) bash script that simply splices in some info from git log -S'KEY' --numstat into the unused list, like so:

    arand@mas:~/annex(master)$ bash ~/utv/scripts/annex-vunused 
    unused . (checking for unused data...) (checking master...) (checking synced/master...) (checking origin/HEAD...) (checking seagate/master...)
    Some annexed data is no longer used by any files:
    NUMBER  KEY
    1       SHA256E-s1073741824--49bc20df15e412a64472421e13fe86ff1c5165e18b2afccf160d4dc19fe68a14.img
                    8f479a4 Sat Feb 23 16:14:12 2013 +0100 remove bigfile
                    0       1       dummy_bigfile.img
                    2988d18 Sat Feb 23 16:13:48 2013 +0100 dummy file
                    1       0       dummy_bigfile.img
    (To see where data was previously used, try: git log --stat -S'KEY')To remove unwanted data: git-annex dropunused NUMBER
    ok
The script:

    #!/bin/bash
    
    pipe="$(mktemp -u)"
    mkfifo "$pipe"
    
    git annex unused  >"$pipe" || exit 1 &
    
    while read -r line
    do
    	key="$(echo "$line" | sed 's/^[^-]*-\([^-]*\)-.*/\1/')"
    	echo -n "$line"
    	test -n "$key" && \
    		echo && \
    		git log --format="%h %cd %s" --numstat -S"$key" | \
    			sed '/^$/d;/git-annex automatic sync/,/^ /d;s/^/\t\t/'
    
    done < "$pipe"
    rm "$pipe"

It would be nice if something like this was available as an option, since it's good way to get a quick overview of what the content is, and if it's safe to drop it.