lost things - I want to track articles

I keep losing articles. Usually the most important articles. And no matter how organised I am with my citation management (woohoo zotero!) it still doesn't know where I last put the paper copy. Is it in the office? Is it at home? Did I leave it on the bus? I don't know! And, yes, I could print out another copy, but I usually scrawl profound notes on the important articles.

I need tiny tracking devices. Pretty colour-coded stickers would be ideal. Linked to my online citation manager. Then when I lose an article I can go look at a map and see exactly where it is. That'd be cool. It'd be even cooler if I could zoom in to see a map of the piles of paper on my desk and I could see exactly where in the piles of paper the article is.