timelapse - Is there a way to use the Nikon D300's timer for more than 999 exposures?

I recently experimented with using the timer in my D300 for a longer car ride (the result can be seen here). That went fairly well, but one thing that bugged me was that the timer stopped taking pictures after 999 exposures, so I had to fiddle a bit with the camera to restart it. Is there a simple way (that I obviously overlooked) to have the camera make more images, preferably until the card is full?