A study published in September last year investigated the speed that certain species of fungi launch their spores. The are launched from what the scientists describe as “squirt guns”. From the article:

Launch speeds ranged from 2 to 25 m s−1 and corresponding accelerations of 20,000 to 180,000 g propelled spores over distances of up to 2.5 meters

While 25 meters/sec is not very impressive, the acceleration is. They travel over 1 million times their own length in 1 second! According to New Scientist magazine:

“The fastest spores travelled more than 1 million times their own ‘body’ length in one second,” says Money. “A 1.8-metre human travelling at 1 million times his or her body length in one second would be travelling at a velocity of 1.8 million meters per second, which is more than 5000 times the speed of sound.”

More videos and information here.

Thanks to Jordan for emailing me the link.