So far there have been a couple of chase scenes in my campaign.
An earlier one had the players on a floating 'liner' style ship (Basically an airship). The ship was ambushed by a bunch of Jadwarri (Skaven) engineered raider vessels, which were small, quick one man skiffs.
The theif in the party made a daring jump (rolling a 20) onto one of the raiders as it raced across the deck in a strafing run. The thief was planning on kicking the pilot out and figuring out the controls, however the psion unleashed a devastating bolt of elecricity at the raider just as the thief landed on the back of it.
The result was the raider skiff spinning wildly with a screaming theif and pilot clinging on for dear life. The vessel then smacked right into the bridge of the airship, and the thief who was on the hind end of the raider was catapaulted all the way to the very end of the ship, bouncing once across a sail and nearly falling off the edge of the shop to certain doom. Luckily he made a stunning reflex save at the last moment to get his claws on the trailing sail and hang on for dear life.
The resulting chase battle between the raiders and PC's/Ship crew is one of the most memorable of any campaign I've run.
The second was another 'skiff' battle much closer to the ground. To this day, the barbarian/ranger of this party is the only person in any game I've ever run who killed 10 people with one arrow.. The first shot of the chase had him over-crit the pilot of one skiff, and have it crash into its companion, wiping out both..