We have all seen curved mirrors at one time or another. Often they are employed in stores, to look for shoplifters.
Some trucks have small curved mirrors attached to their the rearview mirrors.
There are numerous famous instances in art. You may have trouble seeing it, but behind the couple is a curved mirror on the wall. A related phenomenon in art is anamophosis . This applies to two different things really. One is the method of painting something that is meant to be viewed from some funny angle.