A two drawer vertical metal file cabinet, heavy duty. Holds standard patterns 2 wide and the oversize ones turned on their side. It has a full width adjustable divider, like a wall, that I adjust as needed. Everything is sorted by type and I have tabs that show on red cardstock with category name. Current wishful thinking goes at front of top drawer, seldom used, like men's and costume patterns are back of lower drawer.
When I get an overflow I cull back and try to keep myself to this and a plastic shoe box of alleged current projects. Really it's just a drool box.
PDF's I use are generally over sized Lagenlook type stuff. Many are clamped into pant hangers and hanging in the closet or draped over a portable clothing rack. I'm going to put hooks on the back wall of my closet, under the shelf, so they can hang flat against the wall, out of the way.