Here in Minnesota, as far as I know, they were always called snowmobiles. Ski-Doo was just one of the brand names.

I know what you mean, though—the first brand of anything that appears in a given area is likely to have its name turned into a generic word in that area.

To this day, vacuum cleaners are called "Hoovers" in the UK.

In some parts of the US, mainly in the South, I think, refrigerators are called Frigidaires.

And some people in the south call all bottled soft drinks "co-cola"—from "Coca-Cola."

In Minnesota, ATMs are called cash machines. That's because the first company that introduced them here used the brand name Instant Cash. Over the years, "Instant Cash machine" evolved colloquially into "cash machine."

My father used to call all mechanical pencils "Eversharps."

Today Sharpie is turning into the generic term for what we used to call a "Magic Marker" and later a felt pen—but I suppose "felt pen" is no longer appropriate because the points are now made of plastic, not felt. So what is the correct generic term for them? Marker? That seems a bit TOO general.