We have designed and demonstrated a very simple and compact ultrashort-pulse compressor using a single prism and a corner-cube. Our design is significantly easier to align and tune compared with previous designs. Angle-tuning the prism wavelength-tunes, and translating the corner cube varies the group-delay dispersion over a wide range. When tuned, the device automatically maintains zero angular dispersion, zero pulse-front tilt, zero spatial chirp, and unity magnification. The device can easily be built so that its output beam remains collinear with the input beam, and when the input beam or pulse compressor moves, the input and output beams remain collinear