What is your favorite single song from a video game?

There are so many, I'm thinking about doing a top 10 one of these days.
 
My personal favorite would have to be the Song of Storms from Zelda. Not only is it an amazing piece of music, but it just brings back so many awesome memories of playing the two Zelda N64 games with my friends when we were younger.
 
 

Breathing new life into ladder-climbing:

SPOILERS:
 

Either this:
 
 

I have always had a thing for the 1st Mario Bros song...  Its kind of catchy for a 8 bit video game song.
 
 

Mutants on the C64 by Fred Gray. Three channels of sound utilised brilliantly. Sadly this a pretty lo-fi video.

 I won't embed a ton of Youtube vids, because I think the songs are iconic enough that you'll know what I'm referring to.

Ironic hits for me include the end song to Rogue Warrior ("goddamn cockbreath commie motherfucker!"), "Girlfriend" from Brutal Legend and "IN-DE-STRUCT-A-BLE" from Street Fighter IV (but only slightly, because I love that song in a guilty pleasure way too).
 
Someone posted a topic about the best songs from a game soundtrack from last year, and they had "Downstream" from Braid which I called a "simply beautiful" song, which it is.
 
I also love the entire Bully soundtrack, as well as that from Bionic Commando: Rearmed (amazing soundtrack). Finally, this, I feel, is one of the best songs from any video game ever. I assured my non-gamer lady friend that this is the case, but she doubts me. Maybe you guys have my back on this one?
 
 
 
 

The music of Half-Life 2 was almost its own character. 
 

" @Disengage: OOOH boy, you sir... are right on target. I dig it.
 
At the minute? I'll go with the Goldeneye's pause menu beat.
  

"

This was a triumph... I'm making a note here: HUGE SUCCESS.

Someone was kind enough to upload the song below, considering it isn't included with the rest of the music (officially anyways), the only way to hear it was at the first quarter of the game. How kind of that person. I would always play this song in my head when I was talking with someone, just felt right.
  

You don't get much better than the Sonic 2 OST.

Look everybody!  It's the FFVII fan boy!
I like the main theme from Final Fantasy VII.  This is the orchestra version. 
 

I still have a Genesis hooked specifically for Super Street Fighter II: The New Challengers.  The music is still awesome.  The SNES stuff is better sounding to me though.
 
 

  @Whisperkill:

Final fantasy 8, Don't be Afraid

i don't know how to embed it XD

 
I'm not the worlds biggest fan of Halo, but I absolutely love the soundtrack---this in particular: 
 
 

Forever ingrained in my mind.  
 
  

"    @Whisperkill:

   

    
   cannot decide. "

Strangely, it was the song from Wanted: Weapons of Fate. Hearing it just made me feel like a badass assassin, which the game failed at in other parts.
They should have just kept the song going instead of having it die out every now and then.
 
 

I was eating the first time I heard this, very dangerous. That said, choking to death after laughing at this song is an inescapable irony.
 

And as long as we're talking really kickass Sonic Music...
 

Either the Oblivion theme or the Stormwind Theme from WoW.

Here's some more good ones I like:
 
 

Here's some more good ones I like:
 
 

 http://www.youtube.com/watch?v=3G8QywDNCEU
 
Love this.

There are a bunch of different songs I've come to love over the years from games.  Some go back a number of years and others are very recent.  I'm not going to embed a bunch of them since (a) it's dangerously close to YouTube spam and (b) most people just glance over them without clicking them to listen.  So, I'll link a few below which will probably have the same result, but will take up less space on the page.

1. "Hikari" / "Simple and Clean" : Kingdom Hearts  ~  Back when G4 still aired a show called Cinematech, they aired this and another video constantly.  I got hooked on both songs because of this and have had them on my Ipods for years now.  
2. "Fly Like a Butterfly" & "The Concept of Love"  :  Jet Set Radio Future  ~  The entire soundtrack by Hideki Naganuma is fantastic, but these two songs really stuck with me over the years.  They too have been in strong rotation on my Ipod since early 2000s. 
   
3. "Brand New Days"  : Shin Megami Tensei: Persona 3 FES  ~  This one is relatively new to my playlist, but I really like it.  Whenever I hear it, I am reminded of the game which I also love.
4. "Reach Out to the Truth"  :  Shin Megami Tensei: Persona 4  ~  Basically, I've have this song drilled into my psyche after so many battles.  P4 is among my favorites (behind P3) so, this one was a "no brainer" to mention.  "Mass Destruction" from P3 FES (the battle song), is also etched into my skull, but "Reach" is a slightly better song in my opinion.
   
5. "Reign of the Septims"  :  Elder Scrolls IV: Oblivion  ~  Not since "Carmina Burana, O Fortuna" has their been a song I think that so perfectly encapsulated the majesty of the traditional fantasy genre.  
6. "Wishing for an Eternal Sky"  :  Skygunner  ~  About the same time G4 was bombarding me with Utada Hikaru's song, they also put this charming trailer into heavy rotation.  It has since become my number one song from a video game.  Below is the video to this great song.  
   
    
   

I'm gonna cheat a little 
   
  

  Or:

there's a few
Kraids Chamber - Metroid
It's one of those songs you can listen to forever as long as you're playing a game, it evokes an atmosphere which makes it hard to stop playing.)

One that really stands out to me is the Gerudo Valley song from Ocarina of Time 
I remember just going there just so I could listen to the song.  
 

" One that really stands out to me is the Gerudo Valley song from Ocarina of Time 
I remember just going there just so I could listen to the song.  
 

  Just to add to the Youtube spam =D "