What is fortified wine?
Sherry, port, marsala, vermouth.
Sweatpants
Party!
If anyone can tell the difference between vodkas (as they are drinking, not talking hangover here), other than room-temp shots, they are either Russian or lying.
EDIT: I'm hammered riht now, and I'm no sommelier, but fortified wine is basically wine with liquor added. Usually brandy. Wine can only handle so much of a percentage of alcohol. When the yeast eats the sugar to ferment, the products are alcohol and C02.
If you were to make a brut the old-school way, you would cork it and let it all stay in the bottle, carbonating the finished product. This is why champagne has a wire thingy on top of the cork. The you would freeze the very top of the bottle while it is upside down, and pull the cork and the extra crap out, then reseal it.
Ports are sweeter and richer in alcohol content because the fortification halts the fermentation process and adds alcohol. Usually they are 20% abv or so.