Cool refi calculator helps you determine if you should refinance…

Enter your current mortgage rate, how long you plan to live there, etc  and the calculator determines how far interest rates need to fall before you should refinance again.

I have a 4.5% interest rate and I was considering refinancing again to get a 4% rate.  Turns out, bad move.  If you have similar thoughts, I recommend checking out this calculator.  Visit it at http://zwicke.nber.org/refinance/.