Optical fiber storage loops storing packets of high-speed optical return-to-zero data have been demonstrated. Storage times greater than 30 minutes have been achieved. A basic storage loop design, demonstrated at 20 Gb/s, resembles an active-passive harmonically mode-locked fiber laser. A new modulation technique, rational-harmonic modulation, has been used in a similar storage loop design to achieve 50 Gb/s storage, using a modulator with only a 13 GHz 3 dB bandwidth. A 10.6 Gb/s all-optical storage loop has also been demonstrated, in which the electro-optic modulator has been replaced with a semiconductor diode amplifier which is driven by an optical clock.