I bought a huge bag of Jodi Barrows books and rulers about 7 years ago ... she was a guild guest speaker. They are still wrapped in plastic, spent over $100 ... don't know when I'll ever use them. They sure looked like a great investment that night.
I've also purchased quilt DVDs and other stuff that I've never used. Could kick myself, but I'm not dead yet so I might use them or still kick myself later