Your best 'first listen' ever

Isaac Hayes' Hot Buttered Soul. I was staying that summer with a friend who lives in Yakima, a small town over the mountains from Seattle. He lived in a tiny rundown house whose interior was dominated by the drumset that took up most of his living room, and he was a beast on the drums. I had it turned up on his nice stereo system, he comes home in the middle of "Hyperbolicsyllabicsesquedalymystic", hears it, immediately jumps behind his drumset and starts jamming along with it.

There's a number of albums that have utterly floored me on first listen, but probably the most memorable was Agaetis Byrjun by Sigur Ros. Just felt like every song seemed to one up the previous one in terms of beauty and grandeur and eventually left me spent by the end of it.

Enter the Wu-Tang at 14
Everybody Knows This is Nowhere at 19
Salem's King Night at 30 (I know)
Floating Points' Elaenia at 36