The sequel to
Micro Machines (no, really!), a
Sega Mega Drive top-down racing game developed by
Codemasters (back in the days before they sucked). The game simulates racing tiny
model cars around
household environments - a premise which may sound strange, but allowed the developers lots of
freedom to dream up novel uses for
everyday items as
obstacles on the track.
Some of the many environments included a garden, a breakfast table (milk and orange juice slicks ahoy), a toolbench, a snooker table, and, famously, a toilet seat. Of course the players would have appropriate vehicles for each location, including dune buggies, scramble bikes, motor boats, hovercraft, tanks, sports cars and helicopters.
MM2 expanded on every part of its predecessor (which was, IIRC, originally a NES game), adding dozens of tracks, vehicles, hazards, characters and playing options. The most technically impressive feature was that the game supported 4 joypads without the need of a multitap - there were two extra controller ports built into the actual cartridge (this was known as the J-Cart system). But the craziness didn't stop there - by sharing each pad between two (close) friends, you could have 8-player races! (Where each pad controlled a team of 2 vehicles.)
Before they bailed out of the 16-bit console market, Codies released a couple of special editions of the game, adding more tracks. Micro Machines 2 still stands as one of the best "social" games ever, beating even the mighty Bomberman series in my book (but that's probably because I suck at Bomberman).
Bonus Trivia Fact : One of the drivers in Micro Machines 2 is supposed to be Violet Berlin (then presenter of god-awful ITV games show Bad Influence). This little ploy succeeded in getting the game some free publicity!