resident evil 5 new ways to get stuff

By finishing the game you unlock different graphic filters to use during gameplay. Once unlocked, go to Bonus Features and buy them for 0 pts. each.

Unlockable How to Unlock

Classic Horror (Black & White) Beat the game on Amateur difficulty
Noise (Grain effect) Beat the game on Veteran difficulty
Retro (Sephia) Beat the game on Normal difficulty

Unlock Infinite Rocket Launcher
To unlock the Rocket Launcher with infinite ammo, beat the game under 5 hours on any difficulty, and turn infinite ammo on under bonus features.

Unlockable Costumes

Unlockable How to Unlock
Chris (S.T.A.R.S.) Complete Chapters 1 - 6 and find 25 BSAA Emblems
Chris (Safari) Complete Chapters 1 - 6
Sheva (Clubbin') Complete Chapters 1 - 6
Sheva (Tribal) Complete Chapters 1 - 6 and find 30 BSAA Emblems

Unlockable Mercenary Characters

Unlockable How to Unlock
Chris (Safari) Get an A Rank or higher in The Village
Chris (Stars) Get an A Rank or higher in Experimental Facility
Jill (Battle Suit) Get an A Rank or higher in Ship Deck
Jill (BSAA) Get an A Rank or higher in Public Assembly
Sheva (Clubin) Get an A Rank or higher in Ancient Ruins
Sheva (Tribal) Get an A Rank or higher in Missile Area
Wesker (Midnight) Get an A Rank or higher in The Mines
Wesker (STARS) Get an A Rank or higher in The Prison

Unlockables

Unlockable How to Unlock
History of Resident Evil Beat the game on any difficulty
Mercenaries Mode Finish the game in any difficulty.
New Game+ Finish the game in any difficulty.
Playing with Sheva Finish the game in any difficulty.
Professional Difficulty Beat every chapter on Veteran
Unlimited ammuntion for a weapon Finish the game then max out the upgrades for that gun.

Weapon Unlocks
Fully upgrading the first weapon of each type unlocks the ultimate weapon of each category.

Unlockable How to Unlock
Gatling Gun (Chris Only) Fully upgrade the VZ61 Machine Gun
Hydra Triple Barrel Shotgun Fully upgrade the Ithaca M93 Shotgun
Longbow (Sheva Only) Fully upgrade the S75 Rifle
M93R Pistol (Samurai Edge Custom) Fully upgrade the M92F Pistol
S&W M500 (Handcannon) Fully upgrade the S&W M29 Magmum

Glitches
Regenerate items

Chapter 2-1, take all the items at the beginning and then Quit the game. Return to the game by selecting "Continue" and you will begin Chapter 2-1 with the items you got before you quit the game, however, the items at the beginning (you took just now) are still at the same place, so you can obtain them again. Repeat the same thing to get as many as you like.
Note: This works on any stage, this is just one example of how to benefit from it.