In 1996, my friend was listening to a Rush CD and I liked what I heard, so I borrowed it from him and got heavy into them. From there I did research on the internet and some guy had a list saying "If you like Rush, check out these bands." Half the bands on the list were prog bands like Yes and Genesis, while the other half were metal bands like Maiden and Dream Theater.
I was a fan of hair metal in the 80's and grunge metal in the early-mid 90's, but this was what opened the metal floodgates for me