If you find chromed bathroom and kitchen fixtures' hard water stains that won't come off easy with regular cleaners, you can try cutting a lemon in half and scrubbing the surface with lemon halves.

According to weblog Broccoli Cupcake, this method removed all the hard water stains on the author's shower after the author was told by cleaning professionals that hard chemicals must be used to remove the stains. The critic acid in the lemon will cut through the stains and works to remove rust stains as well.

[Broccoli Cupcake]