This piece lifts your spirit, gives you energy, and makes you feel heroic     

This is a tough one for me, but one piece which definitely comes to mind is "Gateway to Destiny" from Eternal Darkness, which is one of the most exciting boss-fight pieces ever written!  I'm sure I'll think of plenty of others later, but that's it for now.

cheers,

-avatar!

"Still More Fighting" / "Those Who Fight Further" from FF7 OST / Black Mages springs immediately to mind.  Don't know about lifting my spirit or making me feel heroic, but sure makes me want to throw down on some bad guys!

Runner-up:
Theme of Simon - Dracula Battle
Rush! Issei and Yoshi - Giant Robo 2 OST
4th Movement - Symphony Ys '95
Arthur's Farewell - First Knight OST

In terms of movie music, although it wasn't intended for film but nonetheless it's been in MANY movies, Carmina Burana's "O Fortuna" is always rousing!

cheers,

-avatar!

An unlikely choice, but the allegro testimony themes from the Gyakuten Saiban/Phoenix Wright series are totally amp-worthy in my book -- especially GS1's and GS3's.  I'm split between the two; the pairing of melody and harmony in both Sugimori's and Iwadare's themes are decidedly different, but equally brilliant.  Sugimori's from part one takes the driving "tense theme" motif from the score, places it into the backdrop while imbuing it with a bit of a speed treatment - and it bodes extremely well with the regular testimony theme.  Iwadare's from part three, on the other hand, relies on two distinctive melodies --- both heard in the regular testimony theme -- which cross-harmonize with each other, giving off an interesting combination of moody and upbeat.  Very cool stuff.

Everything on Wangan Maximum Tune 2, 'nough said.

Heh...the moon base music in Paper Mario 2. I played that game for longer periods of time solely because the pace of the music was prodding me to keep on going.

Aside from that, I liked the battle music that played when you controlled Laguna in FF8. That was some pretty pumping music, too. ^_~

Blood pumping battle music to make you feel empowered, and heroic, huh?

Okay, here goes . . .

Wangan Midnight: Maximum Tune's music, is up there, any of the tracks. "Zakat" from the ZOE 2 OST is also really awesome, as well . . .

Eurobeat song, "Gimme the Night", makes me feel like a race king, and I love grooving to this song, on my stereo while playing racing games. Actually, pretty much any Eurobeat tune from Initial D is awesome for car battling (I'm really diggin' "Over the Rainbow" by Powerful T.).

Final Fantasy IX's battle theme was totally rockin', as well . . .

There are so many to list . . . I can't think of them all . . .

Yeah, "Those Who Fight Further" from FFVII definitely gets the blood pumping. Estpolis II (Lufia II) has some great battle themes as well, especially Battle #2 and #3. But, at this point and time, no other game's battle themes have hyped me up more than Shadow of the Colossus. Kow Otani creates some incredible pieces that really motivate me while I'm playing the game. "A Violent Encounter", "Revived Power" and "Counterattack" are probably my favorites of the 13 (14 including the "Final Battle" track not included in the actual game) amazing battle songs in the game.

The normal battle and boss battle themes from Final Fantasy USA/Mystic Quest. I remember imagining how great these would sound played by a rock band before I ever heard "game music" and "remix" in the same sentence. The same goes for perhaps a more unlikely choice: the final boss music from Super Mario World 2: Yoshi's Island.

While not my favorite final boss theme of the Guilty Gear series, "Kill DOG as a sacrifice to DOG" gets the blood pumping the most.

Perhaps it was because it was my first RPG final boss battle, but Final Fantasy IV's "Zeromus" really completed the "final showdown" feel for me. "Meridian Dance" from Secret of Mana/Seiken Densetsu 2 too, for similar reasons.

Hehehe...oh yeah, baby, Eurobeat for car battling. Not as if I play Initial D (or any racing game) much, but I've watched some pretty exciting Initial D races in the arcades. Heck, even for watching the racing in the actual anime...

Off th' top of my head...

Cyber Phantom (Viewtiful Joe 2)
Blizzard Hazard (Viewtiful Joe 2)
Mad Scientist (Viewtiful Joe 2)
Aloha Robo (Jumping Flash)
Hunter vs Hunter (MMX5)
Our Blood Boils (MMX7)
Vs 8Boss (MMX8)
Slave Beast Taka (Shattered Soldier)
Jinmen-Gyo (Shattered Soldier)
Thermosphere (Einhander)
Never Return Alive (Streets of Rage 2)

...I could keep going, but hopefully you get the idea. Orchestras, choirs, that's stuff's all fine for whatever else, but when I'm in 'battle mode,' I want rock, metal, techno, or some combination thereof.

It's not really battle music...but I have extremely vivid images of battles that go through my head when listening to it... It's the credits music from Terminator 3 that are composed of the Terminator 3 Theme, followed by an orchestral version of the original Terminator theme.

Then, the other one that really does it, is one of the final tracks (I think track 29) on some Ehrgeiz Anime soundtrack that I got accidently when ordering the video-game Ehrgeiz. (I've never seen the anime, so I don't know where it goes in the anime either)

~Sky

One that really gets me going, but not one I'd use in my own battle (heh), is 410 - Challenge from FF 10 OST. It's not really even one of my favorite songs. But it can get my blood going, ha.

ATM, Steel of Destiny from Thunderforce 5/6 (in its synth-metal form) is quite high in my list of heroic/pumping tunes.
You can get a good cover version of it there.

You should check the great doujin album "For All FF Lovers" by Preludio, as there's a great medley of 2 Mystic Quest battle themes on it.

Thanks for the recommendation, dma. The preview MP3 sounded really good. Would they sell to Americans, though? I don't see any of my usual import sites selling them.

The Thunderforce cover from S.S.H. was enjoyable as well, thanks.

On the FF:MQ album Sasai arranged all of the battle themes into one and the last castle theme with rock, but they aren't really heavy.

That I do have (albeit in SM form :\). You're right, a little light, but not bad. I think my favorite rendition of the battle theme so far is "Red Cap Assault," a fan remix by Ashane (it was on the now-dead VGmix.com), though that Preludio track sounded promising.