Comment by david-given

Are you thinking of the new flat-tree npm? Because in my 1.3.10 installation, I see this:

    $ find node_modules/ -type f | wc -l
    56278
    $ find node_modules/ -type f | xargs md5sum | gawk '{print $1}' | sort | uniq | wc -l
    8545

That's a lot of duplicate files.