Pilobolus kleinii filmed at 50,000 fps
From a 2008 paper published in the journal PLoS ONE, The Fastest Flights in Nature: High-Speed Spore Discharge Mechanisms among Fungi.
A variety of spore discharge processes have evolved among the fungi. Those with the longest ranges are powered by hydrostatic pressure and include “squirt guns” that are most common in the Ascomycota and Zygomycota. In these fungi, fluid-filled stalks that support single spores or spore-filled sporangia, or cells called asci that contain multiple spores, are pressurized by osmosis. Because spores are discharged at such high speeds, most of the information on launch processes from previous studies has been inferred from mathematical models and is subject to a number of errors.
Two videos viewable at bangocibumbumpuluj, you can download the rest here (scroll down to “Supporting Information”)