I'm wondering what some of your favorite videogame music is that is either entirely piano or heavily features piano.  Here are some I can think of:

Breath of Fire 2 - God of Decadence (Organ)
Chrono Cross - Reminiscence ~ Thoughts not Extinguished
Final Fantasy Piano Collections - Various
Katamari Fortissimo Damacy - Overture
Kingdom Hearts 1&2 - March Caprice and Dearly Beloved
Mother 1+2 Piano Version - Various
Soul Calibur 3 - Peaceful Days (Piano Versioin)
Super Mario 64 - Piranha Plant's Lullaby - Piano Version
tLoZ: The Wind Waker - Farewell Hyrule King
Xenogears - Lost~ Broken Shards and In a Prison of Peace and Regret

Any other suggestion would be great.  I have a vgm radio show and I'm planning on doing a piano themed show, so any suggestion will be helpful, though actual videogame music would be better (as opposed to piano collections) because I'm going to need to 'find' it by Saturday.

Let's see about some of the stuff I have on my iTunes. I'm not including any arranged stuff, since those are fairly obvious.

.hack// Game Music Perfect Collection - BooHooWoo: staff4 [Vol.4 Staff Roll]
Breath of Fire V: Dragon Quarter - Hitoshi Sakimoto: Small Departures
Chrono Cross OST - Yasunori Mitsuda: Reminiscing ~Uneraseable Memory~
Final Fantasy X - Nobuo Uematsu: The Way of Purgation
Final Fantasy X-2 - Noriko Matsueda & Takahito Eguchi: Eternity ~Memory of the Light and Waves~
ICO - Michiru Yamane & pentagon: beginning
killer7 - Masafumi Takada: When the May Rain Comes
Motoi Sakuraba Live / SO3 Director's Cut - Motoi Sakuraba: Motoi Sakuraba PIANO Solo
Samurai Champloo - Masafumi Takada: Yukiwari Ballad
Shadow Hearts II - Yoshitaka Hirota: ICARO -piano arrangement- [Main Theme]
Shadow Hearts Special Sound CD - Yoshitaka Hirota: Lady Theme -piano arrangement- [Shadow Hearts From the New World]
This is NAMCO! - Kenichiro Isoda & Kenichi Mitsuda: Mappy's Lullaby
Wanda to Kyozou - Kou Otani: Memories

My votes go for the Takada, Hirota and NAMCO tunes, personally.

EDIT: if you're going to be doing piano plus other instruments, I highly recommend digging through Masashi Hamauzu's SaGa Frontier II and FFX albums.

Rose Confession from Phantasy Star Online by Yutaka Minobe

This is what I could come up with:

Parasite Eve - Main Theme - Yoko Shimomura
Final Fantasy IX - Loss of Me - Nobuo Uematsu
Metal Saga - Driving to New Folk - Satoshi Kadokura
Chrono Trigger - Sealed Door - Nobuo Uematsu
SaGa Frontier II - Variation - Masashi Hamauzu
Legend of Mana - City of Flickering Destruction - Yoko Shimomura
Shining the Holy Ark - Piano version of Main Theme - Motoi Sakuraba
Biohazard 2 - Secure Place - Shun Nishigaki, Syusaku Uchiyama, Masami Ueda

I don't know about individual tracks, but the Arc the Lad and Brandish piano albums are tops.

I believe you mean "Rose of May."  The above was an initial poor translation that lingered like a bad stench for all these years.

I think 'Hope & Joy Peace & Love' from the Gradius Arcade ST is quite possibly the best piano only VGM song I've heard.  (Note, I haven't really heard all that many).   Very tasteful, and skillfully played ( I have the mental image of someone performing this in one take.  Maybe I'm wrong)

http://www.stormedheaven.com/hope.mp3

I'll have to listen to the other recommendations

My own picks. I don't have a huge investment in the piano, but these are all pretty solid tracks (even if all aren't 100% solo piano).

Last Letter Full Complete Version - Broken Thunder Thunderforce VI
Missing... - Guilty Gear XX
Walk in the Dusk - Guilty Gear XX/X Heavy Rock Tracks (same piece with minor differences between albums)
Way - Guilty Gear Original Sound Collection
There Were 30 Days in September - Sakura Relaxation
The Light Moaning in the Darkness - Suikoden V
You'll Never Be Alone, Abbey, The Daughter of Three Treasure Hunters - Wild Arms Piano Collection -feeling heart-
Rising Red - King of Fighters 96 Arranged
Rose of May - FFIX
Decisive Battle, Raid - FFX
Interludium, Zauberkraft - Saga Frontier 2

"Last Letter Full Complete Version - Broken Thunder Thunderforce VI"
Man this one brings chills to my spine (but then many tunes do), and almost tears to my eyes sometimes (yeah i'm a sissy alright ).

Wow, thanks for all the suggestions, maybe I'll have to do two shows!

And the Genso Suikoden Piano Collections are also up to par!

Like I said, I'm not a big piano fan, but everything about that track does the same to me too. If I were picking a favorite from my list, that would be the one (it was the first piano VGM piece to come to mind).

To be honet, there's so many good ones I can't remember them all. But one that comes to mind that hasn't been said is the piece from Lunar: The Silver Star. (Also, the one from Silver Star Story is good).

-Joshua

I will say Gradius in Classic piano pieces, since i listened to them quite a bit.

KH/KH2 - Dearly Beloved
The entirety of FFX-2 Piano Collections
The entirety of SaGa Frontier 2 Piano/Rhapsody
and uhh...damn there's a lot. I'm not even gonna try. I'll edit this post when more come to mind.

Ramza

Well, there's a lot that I'd like to list, but I happened to be listening to Yoko Shimomura's Parasite EVE OST when I noticed this recently revived thread, so I'll start with that.

Parasite EVE - Various
Atelier Viorate - The Mudship Sinks at Culotte Village
(Yes, there's a difference in the characters for "Carrot" village and "Culotte" village on the case)
Atelier Iris: Grand Fantasm - Ghost Girl for Grand Fantasm
(It has more strings, percussion, and winds than previous incarnations, but it's still piano-centric, IMO)
Atelier Elie: Unknown Origin - Anything on disc 2 All piano, all beautiful

-
I'll edit this post as I slowly sift through my collection.
Yes, I'm somewhat GUST-obsessed. It's a good thing. Really.

Both "Shion"s from Xenosaga Episode 1.
I just love the Kokoro melody.

im surprised no one mentioned Johnny C Bad

Another vote for Primal Eyes, the Parasite Eve OP.

The delightful arrangement of Kefka's Theme, of course, from FFVI Piano Collections.  (After the first ten seconds.)

I'd recommend the arrangement of Dreams, Dreams (NiGHTS) that appears on the SEGA Piano Nocturne CD if it was just a little uniformly tighter...the chorus part is beautiful, but what corresponds to the verses is a little off.  At least to me.

I know the original reason for this thread has long passed, but I just had to say that I just got the FF X-2 Piano album. WOW, I don't think I've ever been so attracted to an album initially, especially considering that I've never even played the game or heard the original soundtrack.

I love it!

-Kevin