Hipsters may consider dogboarding to be way cooler than horseboarding, but both pale in comparizon to "spider-boarding" - a technique that has been used by mantidfly larvae for millions of years.
The larvae of most mantidfly species are fussy diners – they only eat the eggs of spiders. That seems like a dangerous enough strategy, for spiders are formidable hunters. But it gets crazier – some mantidflies find spider egg sacs by hitching a ride on the backs of adults... The “spider-boarders” can’t chew through the egg sacs. Instead, they ensure that they get inside the sac as it is being built. They climb aboard passing females, wrapping themselves around the base of their abdomens so they can’t be caught.
The photo above, by Michael Ohl of Berlin's Museum of Natural History, shows a spider embedded in a 44 million year old piece of amber. "And there, latched onto its underside just as its modern relatives do, is a mantidfly larva... it’s facing to the right and you can clearly see the three legs on its right side."
Additional details (and a photo of an adult mantid-like mantidfly) available at Not Exactly Rocket Science.