Stubbs the Zombie in Rebel Without a Pulse

Around the time where you are introduced to grenades/the barbershop quartet enemies there will be a couple jeeps that will be driving around. The Jeeps are incredibly floaty to control so either the enemy will directly run into you or accidentally fishtail into you. You can also use the grenade to blast the jeep onto yourself, and there are MANY more vehicles after this segment, so don't stress if you miss this the first time.