I learned about the Greenland balance stool from the book Building the Greenland Kayak by Christopher Cunningham, the editor of Sea Kayaker magazine. The Greenlanders used the balance stool to develop balance for tippy kayaks. Most modern kayaks aren't very tippy, but I thought that when I occasionally watch television, I could at least make that time more productive by sitting one of these stools to improve my balance.

The book gives instructions on how to build a balance stool, but all that you really need to know to build one is that the rockers are 12 inches wide and sweep up 1 1/2 inches on each side. I built mine in a few hours with $25 worth of red oak from a home improvement store.

It's a lot of fun to sit on and really does feel like a tippy kayak.