I absolutely failed at this last year
although looking back over the year, I only bought one hank of yarn (for a scarf yet to be started), four skeins of yarn for an afghan I am trying to finish, 2 skeins for learning socks, and about 10 skeins of a clearanced yarn which I've changed my mind about what I want to do with it.
Okay, that was worse than I thought, especially since I don't have any finished projects to show for it.
(The more I put down the more I remembered something else I bought.
Anyway, put me down again and if I finish ONE of my projects out of yarn from my pre-2009 stash, I'll consider it a success!