Homeownership is the largest wealth-building vehicle in the country. I could roll my equity into a new home at double the rate I'm getting, but I'd rather keep my bottom-of-the-curve rate and have the house increase in value for years. By how much it's gone up since I bought just a couple years ago, it's a virtually risk-free investment. 

But personal finance is not my specialty, it's been a while since I've looked at these figures.