What is the best way to play Mario Kart Double Dash with 8-16 people?

I think the easiest and cheapest way to do it would be with the GameCubes. You can buy them and controllers on eBay and yard sales for cheaper and cheaper every day, whereas the Wii is newer and will continue to stay at a higher cost for a while.

Either way, if you're comparing cost-wise, I would just look up both on eBay, Amazon, and simply to Google to find the cheapest of each you can get and then just to compare prices and just buy the cheaper.

The PC option wouldn't really be worth it because the experience is a lot different since you'd be emulating it somehow. The GameCube would still apply to other games too since you can always just buy another game for it...