What a wonderful way to save some money. I looked into this with my mortgage company. They have several different options...PayPlan12, PayPlan24, PayPlan26 (sounds like BIKE), and PayPlan52. The problem with all options other than the "default" PayPlan12 is that they charge a transaction fee each time you pay and these can add up to $20 a month depending on the plan. I suppose this might be one time where I would consider paying a small upfront fee to save LOTS of money in the long-run. But then again I am 29, living in Silicon Valley where a 2/1 condo goes for more than $500K.....so I may just play the equity game since I don't see myself staying in the condo for more than 5-10 years.