most memorable soundtrack you ever heard in a game

Braid and Bastion

Tetris Theme and mario bros theme

Metal Gear Solid for that covert espionage feel. Resident Evil and its calming save room soundtracks.
Deus Ex Human Revolution for capturing that cyberpunk essence. (Hope Cyberpunk 2077 cranks it up to 11.)
Akira Yamaoka's work in Silent Hill. The soundtrack True in Silent Hill 2 gives me chills.
Anything from Shoji Meguro(amazing guitar skills), Yasunori Mitsuda(Chrono Trigger), Jesper Kyd plus many more.
Also, Far Cry 3's main theme is amazing.

Assassin's Creed 2 (Original Game Soundtrack) - Ezios Family

https://www.youtube.com/watch?v=O0i6YFrSs6c

https://www.youtube.com/watch?v=LQSsq7HCNHw - Lotus Turbo Challenge 2 Amiga Very Memorable for me.

Either the russian Pirates of the Caribbean game or FTL

Mega Man and Phoenix Wright: Ace Attorney

Sonic and Resident Evil Trilogy

https://www.youtube.com/watch?v=d3QhE07YXbE

It hardly qualifies as the most majestic or evocative music I've ever heard, but the soundtrack to Beyond Good and Evil will remain with me to the bitter end. Just something catchy about it.

Propaganda! buh-bum-bum-bum...

EDIT: Also have to throw in a nod to Mirror's Edge. The theme is particularly superb, Still Alive by Lisa Miskovsky.

I agree with MGS 1.

And Crisis Core.

Thw Best Is Yet To Come From Metal Gear Solid 4

legacy of kain and Shadow of the Colossus

Probably either Giana Sisters: Twisted Dreams or the Devil May Cry games.
There are a lot of other really good soundtracks too though- the Serious Sam games, the Gundemonium Collection, Painkiller, Portal 2, Half-Life 2 and episodes, Super Meat Boy, Sequence, Awesomenauts, Borderlands 2- they all also have great soundtracks.

Red Dead Redemption

Hotline Miami!

One of the best soundtracks I have heard for a game.

Nier, Zelda and Bastion.

Castlevania II: Simon's Quest - Bloody Tears, awesome music for not that awesome game :)
WHAT A HORIBBLE NIGHT TO HAVE A CURSE!

Adventure by Zain Effendi.

Silent Hill 2 and Alan Wake

https://www.youtube.com/watch?v=W2CzIcNwvTw

When this world is no more
The moon is all we'll see
I'll ask you to fly away with me
Until the stars all fall down
They empty from the sky
But I don't mind
If you're with me, then everything's alright

Alan Wake has a pretty good soundtrack as I remember it.

Halo, brother in arms or the one by breaking benjamin.