Buying/Selling a Home or Car
Bankrate.com: A good source for finding current average money market fund rates, CD rates, and checking account rates. The site also has a mortgage payment calculator that will show you how much your mortgage will cost per month, how much of every payment is interest, and how much pays down the principal balance of your loan.
Edmunds.com: A good source for information about buying new and used cars; includes car reviews.
Realtor.com: The National Association of Realtors' Multiple Listing Service search engine allows you to search literally millions of homes for sale.
Yahoo! Real Estate: Yahoo's real estate page provides useful real estate information.
LeaseGuide.com: An online guide to leasing a car.