Here goes:

Mass Effect
Halo 3
Eternal Sonata
PGR4
GR:Advanced Warfighter
GR:Advanced Warfighter 2
Quake 4
Prey
Condemned
Splinter Cell Double Agent
Call of Duty 2
Call of Duty 4
Dead or Alive 4
Blue Dragon
Virtua Fighter 5
Lost Planet
Lost Odessey
Guitar Hero 3
King Kong
Rainbow Six Vegas
Dead Rising
Perfect Dark Zero
StuntMan Ignition
Rockstar Table Tenis
Gears of War
BK: Big Bumpin
BK: PocketBike Racer
BK: Sneak King
Kameo
Oblivion + Shivering Isles
Bioshock
Enchanted Arms

Live Arcade Games:

Aegis Wing
Alien Hominid HD
Assault Heroes
Band of Bugs
Bejeweled 2
Carcassonne
Castlevania: SOTN
Catan
Commanders : Attack
Contra
Doom
Double Dragon
Ecco the Dolphin
Galaga
Geometry Wars
Golden Axe
Heavy Weapon
Hexic HD
Marathon: Durandal
Marble Blast Ultra
Mutant Storm Reloaded
Pac-man
Prince of Persia
Puzzle Quest
Rez HD
Scramble
Small Arms
Sonic the Hedgehog
Street Fighter II' HF
Streets of Rage 2
Texas Hold'em
TMNT 1989 Arcade
Ultimate Mortal Kombat 3
Undertow
Yaris

Dead or Alive 4
Ninty Nine Nights(like that game a little)
Tenchu Z(crap)
Oblivion.
Perfect Dark Zero

Would have been SW2:E 360 version but I can't find that anywhere.

SW2:E - what game is that? You should seriously consider getting Bioshock and Lost Odyssey. Don't go by the demo for Bioshock (wasn't really impressed with the game until after I bought it and played through it). Both are top notch games.

Samurai Warriors 2: Empires. At this point in time(RL issues) I can't buy anymore games for the 360. Lost Odyssey does look like a rather nice game.

Holy crap, LM, that's a lot of games.

XBLA:
Aegis Wing
Alien Hominid HD
Bankshot Billiards 2
Bomberman LIVE
Boom Boom Rocket
Carcassonne
Castlevania: SOTN
Contra
Double Dragon
Every Extend Extra Extreme
Geometry Wars
Hexic HD
Lumines Live
Marathon: Durandal
Prince of Persia
Puzzle Fighter HD
Puzzle Quest
Rez HD
Robotron: 2084
Small Arms
TMNT 1989 Arcade
Undertow
UNO
Yaris




Xbox Originals:
Fable
Psychonauts


360 games:
Bioshock
Call of Duty 4
Devil May Cry 4
The Darkness
Guitar Hero 2
Guitar Hero 3
Halo 3
Lost Odyssey
The Orange Box
Oblivion

Everything else I've had, i've traded back in.

Blue Dragon
Eternal Sonata
Dead Rising
Bioshock(somehwere)
Mass Effect
Enchanted Arms
Ghost Recon
Rainbow Six Vegas
Call Of Duty 4
Oblivion and Shivering Isles expansion.
Crackdown
Hitman
Prey
HL2 The Orange Box
Condemned
Conan such an underated game I loved it requires a fair amount skill on the higher difficulty levels
Command and Conquer 3
Lord Of The Rings BFTME 2

Lost Odyssey in less than two weeks.

I have three Xbox Live Arcade games but I can't remember for the life of me what they are, they were free but I don't bother with them.

Hey Verner how good are you in Contra? I'm missing 2 achievements in that game and one of them is to beat the game online with another person. I tried getting it a couple of times, but everyone I've played with sucked and lost all their continues on the first stage. The other achievement is to beat the game with 1 credit so I doubt I'm going to get that one. I also see that you have double dragon. I don't have many achievement in that game so hit me up if you ever want to go through it.

I'm not to big on selling my games so my collections tend to get pretty big. I also love buying games when they have the buy 2 get 1 at toy's r us or Gamestop (some of those games on my list are still shrink wrapped). I also have 12 xbox games. My biggest collection is for the PS2. I have close to 100 games on it.

I'm okay at the game, I wouldn't say I'm great at it or anything. I think I've only beaten it once. >.>

Yeah, I have that problem with a lot of my PS2 games, most of them are shrink wrapped as well, I just don't have the time to play them. But I got into this habit of selling back my games if I haven't touched them, even though I'd love to keep them.

GAMES
Call of Duty 4
Hitman: Blood Money
MOH Airborne
Rainbow Six Vegas
Kane & Lynch: Dead Men
Assassin's Creed
Guitar Hero II
Naruto Rise Of A Ninja
Marvel Ult. Alliance
Oblivion
Halo 3
G.R.A.W.
Need for Speed™ Carbon
F.E.A.R.
Crackdown
Tenchu Z
Madden NFL 07
Gears of War
Overlord
Transformers: The Game
DEAD OR ALIVE 4
Tomb Raider:Legend
Battlefield 2: MC
PGR 3
Kameo
DEAD RISING
Perfect Dark Zero

XBOX LIVE ARCADE
Arkadian Warriors
Zuma
Geometry Wars Evolved
Contra
Prince of Persia
Castlevania: SOTN
Undertow
Metal Slug 3
Gauntlet
Yaris
Heavy Weapon
Catan
Carcassonne
Screwjumper!
Time Pilot
Band of Bugs
Aegis Wing
Cyberball 2072
EXIT
Sonic The Hedgehog 2
Sonic The Hedgehog
Tetris Splash
TMNT 1989 Arcade
E4
Pinball FX
Marathon: Durandal
Root Beer Tapper
Mutant Storm Reloaded
NEW RALLY-X
Wing Commander™ Arena
Joust
Worms
Assault Heroes
Missile Command
Rush'n Attack
Golden Axe
Marble Blast Ultra
Paperboy
Small Arms
Hexic HD
DOOM
Bejeweled 2

That's pretty awesome Durandal. You actually have more Live Arcade games than me . I didn't think many people played them around here( aside from Xianyloanthe and Verner), but I'm gladly proven wrong! Heavy Weapon rocks.

Wow you guys are hardxcore.

Lost Odyssey
Rock Band
Blue Dragon
Eternal Sonata
Beautiful Katamari
Viva Pinata
Oblivion

Andddd that's about it. I would buy more but I don't care for more. I would also play more, but alas the system is in OC while I'm in San Diego.

Marvel Ultimate Alliance
Forza MotorSport 2
Halo 3

All of which I'm just giving to my brother, and I don't feel like buying more for my 360.

I love COD4 and Dead or Alive 4.

Indeed. I'm really into the arcade. Microsoft is definitely making a lot of money off of this awesome concept. Even though I think it's a major rip off, I still buy the Microsoft points and spend the hell out of them on Arcade Games. It pisses me off that they made some of the games free after I had bought them though. I don't like that concept... Lowering the price is understandable, but completely free for people after others have already bought it is just dumb.

Games:
Dead Rising
Overlord
Condemned: Criminal Origins
Mass Effect
Gears of War
Lost Odyssey
Orange Box
The Darkness
BioShock

Games i had:
Lost Planet
Kameo: Elements of Power
Crackdown
Assassin's Creed

XBLA:
nothing yet.

dead rising
f.e.a.r.
oblivion
forza motorsport 2
marvel ultimate alliance
lost planet
nba street homecourt
rainbow six vegas
halo 3

There are a couple of games that are still free such as Agesis Wing (great game) and Yaris(crap). I'm also sure you should also have Hexic.

I think Castlevania SoTN is free now as well?

can anyone post a list of games that are free now?

as for great games on live arcade, I would highly recommend Rez HD. This game is very different (even though it is a remake) and very good.

Why would SoTN be free?

Why do they make any of the Arcade games free?
Doesn't really make sense but Microsoft is Microsoft...

Halo3
COD4

and my bro bought NHL08

the reason why i don't have arcade games is because i didn't have XBL. i bought my 360 used, and the original owner had Hexic, but when i deleted that user's file- i couldn't access that game.

but now that i have a month's gold pass [to download some dl-content], i have Golden Axe and Castlevania: SotN.

i, too, would like some of those free games...