My partialy annotated library of ~200k items & 6M tags is nearing 1Tb disk space total with items tagged a couple hundred times each on average. I feel the mess

My partialy annotated library of ~200k items & 6M tags is nearing 1Tb disk space total with items tagged a couple hundred times each on average. I feel the mess of tables pain right now, but cannot see a more appropriate classification system than (arbitrarily super- or sub-tagged) tag collections to express the arbitrarily nested, potentially recursive relations. Same as parent, if anyone has a brilliant idea, I'm taking. Edit: See http://www.opencypher.org http://www.opencypher.org