Oh man, I get a little misty-eyed looking at these cars. A bucket full of Hot Wheels cars will keep that little guy enthralled for hours! Pro tip: if you want to see his eyes really light up, make a "ramp" that leans against a chair for him to race the cars down on!
Happy memories here, too. My fave car was a blue Ford GT40, long lost.
Get him a roll of track, and introduce him to the joy of stairs.