I was also told you can have someone buy them from you for a penny. How is that for an old wives tale!
I had a wart on my finger years ago, and, though not a plantar wart, it was very stubborn. I was told that they would need to do surgery and that I would probably have a chunk out of my finger for the rest of my life. While I was still pondering the loveliness of this option, I started acupuncture for infertility. A few sessions later the wart was gone. I have no idea, because I kept forgetting to ask my acupuncturist, if he was treating the wart or if it was just a nifty by-product of other treatment, but, in any event, you might want to call up an acupuncture clinic and see if they know anything.