Don't forget the Commodore 64 music . One of the finest 8-bit music was created for C64's SID-soundchip, I think:

http://www.youtube.com/watch?v=sl2bsmLbbus&feature=related

http://www.youtube.com/watch?v=N-fPDD1mUXA

http://www.youtube.com/watch?v=vMJjqVB9JCM&feature=related

http://www.youtube.com/watch?v=Mafip6Am99c&feature=related

If we're talking Commodore 64 then I have no choice but to post this little classic.

I have much too many to list - there's about 150 NES tunes on my MP3 player right now. Castlevania, Ninja Gaiden, Double Dragon, Blaster Master, and many others. Odd thing is, I love the Mario games, but the music was never all that great compared to what other NES games have done.

What I'm impressed with is how people are making 8-bit remixes of famous rock songs and such now - they're all over YouTube.

Wicked Child (Level 3) from Castlevania. Holy crap, that song is the best song in 8-bit history, knocking out the Mario songs and Vampire Killer (Level 1), which was also in Castlevania. Bloody Tears from Castlevania II was awesome, but it still doesn't compare with Wicked Child or even Heart of Fire (Level 5 of Castlevania). Beginning (Level 1) of Castlevania III was pretty sweet though.

Zelda II's opening theme was also amazing. So was Batman's Streets of Desolation (Stage 1). Earthbound Zero [Mother] also contains Pollyanna, a happy, upbeat song that ranks as the franchise's third best, behind Porky Means Business! and Otherworldly Foe. Too bad those two songs were 16-bit... sniff

Regardless, if you want kick@$$ 8-bit music, the Castlevania trilogy is your game.

@24 Oh, I agree I agree the Castlevania music is some of the very best out there. Wicked Child, Vampire Killer and Bloody Tears are some of my favorites as well. And I love most of Castlevania III's music. By the way, the fully orchestrated Castlevania song from the the Play! concert is fantastic if you haven't heard it - great mix of Vampire Killer and Wicked Child.
Here is the link: http://www.youtube.com/watch?v=TvEHTT4ixSw
I like to make music mixes and combine 8-bit songs with their fully orchestrated counterparts. It makes for interesting listening.

@23 Interesting point about rock songs being made 8-bit. I have heard about that - I'll need to do a little more exploring on YouTube. I have to say that I really do love Mario music though! For example the closing theme in Super Mario 3 is just awesome, and super catchy. There's also some great translations of Mario music. Like the Super Mario World theme (okay that's 16 bit I admit) super-jazzed up and played by brass instruments! Really makes me appreciate the songwriting that went into these classics.

I am the composer for an upcoming 8-bit adventure game called Virgin Blade, which is going to be like NES Zelda but with more RPG elements. If you all don't mind, I'd like to share two songs called "Dread" and "Subterranean Gloom".

Dread: http://www.youtube.com/watch?v=fMFqPZ0xhTU

Subterranean Gloom: http://www.youtube.com/watch?v=3C5dPkVVsGI

My favorite song from 8-bit Ninja Gaiden is Act IV-2 because it is so melodic and driving. Ninja Gaiden's soundtrack in part sounds so good because of the wonderful drum samples. The drums sound absolutely awesome.

great stuff up there, i just want to mention the guitar solo in T&C Surf design. its tough to get when surfing

Burai fighter great sound great game very underated still play on my home build cabinet.

Actually a lot of those are just normal songs someone put into this program whose name I can't remember that spits them out as 8-bit music. Pretty cool, but nothing to really be impressed about. Someones that are made by an actual person are really cool if not better. Although I won't deny a lot of those 8-bit remixes made through that program are cool.

Castlevania 2 Simon quest (every track)
Metroid - kraids lair
Battle of olympus (every track )

Blaster Master has one of the best soundtracks I've heard in a NES game, almost as great as Koji Kondo's compositions.

The 8 bit jingles of the following games will be stuck in my head forever.
Shadow Gate
Deja Vu
Ninja Gaiden 2
Faxanadu
Metroid
Castlevania: Simon's Quest
Dragon Warrior
Mega Man 3
Iron Sword
Solar Jetman
Metal Gear
Legacy of the Wizard

NES
-Super Mario Bros. 2
-Super Mario Bros. 3
-Kirby's Adventure
-Ice Climber
-Balloon Fight
-The Legend of Zelda
-Final Fantasy III
-Mother

GB / GBC
-Super Mario Land 2 : 6 Golden Coins
-Pokemon Red and Blue
-Pokemon Gold and Silver

I've never played the original Mother game, but I've always loved this track:

And this is one of my favorite tracks from the great Castlevania soundtrack although, unlike many other tunes from that game, it really hasn't popped up much since the original game:

I dare you to tell me this is not theee best NES track!