About a decade ago, a very remarkable optical system was devised by Offner, mainly for 1:1 projection lithography of microcircuits. This system contains only two reflecting surfaces, which are spherical. The aberration properties in this system are very remarkable in that all the primary and several secondary aberrations are eliminated. The system is completely achromatic since no refraction is involved. In this short paper we make some suggestions for the use of this system in several other areas of optics.