git-show-all-objects.sh

#!/bin/sh

set -e

cd "$(git rev-parse --show-cdup)"

# Find all the objects that are in packs:

if [ "$(ls -A .git/objects/pack)" ]
then
	for p in .git/objects/pack/pack-*.idx
		do
    			git show-index < $p | cut -f 2 -d ' '
		done
fi

# And now find all loose objects:

find .git/objects/ | egrep '[0-9a-f]{38}$' | \
  sed -r 's,^.*([0-9a-f][0-9a-f])/([0-9a-f]{38}),\1\2,'

OS X 10.9's version of sed doesn't understand -r, but awk works just as well for this. I've provided an alternative in my fork.