This year, I'm finally moving, so I have a small subset of stash with me. I've started a new file that shows how many miles I have as well as how many projects I have going on, finished, and how many queued based on available supplies. All of the yarn that I have, aside from project scraps, is tied to a semi-specific project (Blue Socks and Purple Socks still need patterns!), so it should be pretty comprehensive. I'm updating it every time I finish a project or acquire new supplies.
So far, I've learned that if I have a small stash, my brain says, "You need more, now!" I've already bought a significant amount of yarn this year, thanks to my apparent need to have more stash than is reasonable, a couple of interesting mystery patterns (I'm a sucker for a mystery or -along), and great sales/coupons from JoAnn's. Hopefully I like Deborah Norville Serenity Sock - I've got a lot of it!
Also I like charts and graphs. And colors.