Yahoo Search has quietly added a new quick answer to their search results for mortgage related searches. When you search for [mortgage calculator] or similar searches, Yahoo will show an interactive mortgage calculator at the top of the search results, above the organic results but below the search ads.
The calculator works for both home purchases and/or refinances. Asking you to specify the home value or mortgage amount, the loan term, interest rate and down payment. The output will show your monthly payments in principal and interest and even break down your tax and insurance payments.
Google added a mortgage calculator search answer about a month-and-a-half ago. While Bing does not offer one yet for a search on [mortgage calculator].