Well... I recently went and entered my entire game collection into a spreadsheet. It's on Google Docs. If you wanna see for yourselves,
here's a link.
Or... if you prefer a PS3/PSN-only list... I think these are all the ones that have multiplayer components.
PS3
Battle Fantasia
Bionic Commando
BlazBlue: Continuum Shift Extend
Burnout Paradise
Call of Duty 4: Modern Warfare
Demon's Souls
Far Cry 2
Fatal Inertia EX
Killzone 2
King of Fighters XIII
MAG
Marvel vs. Capcom 3: Fate of Two Worlds
Mortal Kombat vs. DC Universe
Skate 2
Soulcalibur IV
Ultimate Marvel vs. Capcom 3
Unreal Tournament III
PSN
Bomberman Ultra
Castle Crashers
Crash Commando
DC Universe Online
Dead Nation
Elemental Monster Online Card Game
Free Realms
Hustle Kings
Inferno Pool
Lead and Gold: Gangs of the Wild West
Magic: The Gathering - Duels of the Planeswalkers
Mahjong Tales: Ancient Wisdom
Marvel Pinball
Marvel vs Capcom 2
Mortal Kombat II
Plants vs. Zombies
Scott Pilgrim vs. The World
Simpsons Arcade
Street Fighter III: Third Strike Online Edition
Super Puzzle Fighter II Turbo HD Remix
Super Street Fighter II Turbo HD Remix
Swords and Soldiers
X-Men