Hours and hours of multiplayer action.
I admit that this one does not have me running to go back and hook up my N64 again, but I really enjoyed it for the first couple years after the purchase. The one-player mode has a number of tracks and races to master with one of the eight selectable characters. Each character actually has strengths and weaknesses, so there is strategy before the start of the race.
The multiplayer has the combination of having both a racing and battle mode. The racing allows for the four-player split screen action on any course from the single-player game. The battle mode includes four separate tracks that cage you and your opponents together in an all out melee.
And there have been newer installments of this series, so just remember where it came from.