For me it was Epic Pinball on a Sound Blaster 16. Playing Duke Nukem 1 was awesome and all(wish I could go back) but when I heard the intro to Epic Pinball come out of these speakers:

https://assets.superhivemarket.com/store/product/190602/imag...

It was one of those moments where computers blew my 8 year old mind, I was never the same.