Sorry, I don't recall that thread either. Similar to nn4jw, I use hanging file folders but, put them in a file box with a lid. That tends to keep out the dust and other flotsam and jetsam floating around my shop. Mine is similar to this but not the same one: http://www.walmart.com/ip/Storex-Portable-File-Box-with-Organizer-Lid-Legal-Letter-Black/42351880
Good luck in your search.
Sorry I got too many tools so I have run out of room for a filing cabinet.I have a two drawer file cabinet to give away, just come and get it.
My machine & tool manuals are in 3 ring binders by category. I store these on a shelf towards the rear of the shop were there is less dust.
Pop