Sony's detailed what it's calling one of the biggest updates ever for the US PlayStation Plus service, which includes a beta for PSN spin-off, Red Faction Battlegrounds.

Arriving on September 21, the update adds free games (Zen Pinball, Echoes - minis, and Syphon Filter 3), a 50% off sale for Cuboid, early access to RTS Sword & Soldiers and more.

Here are the goods:

Free Games
Zen Pinball
Echoes - minis
Syphon Filter 3 - PS One

Early Access Game and Demo
Sword & Soldiers
Free Game Add-on
High Velocity Bowling - Move Compatibility Add-On

Free Themes
Shades of Autumn Theme

Discounts
Cuboid (50%)
Savage Moon (50%)
LittleBigPlanet: Monster Costume Pack (50%)

Discounted PS One Games
PS One Imports
Cho Aniki
Gaiaseed

Free Avatars
LittleBigPlanet Avatar - Hugo
LittleBigPlanet Avatar - Marvin

Last Chance, Get Them While You Can - Coming down on September 21:
Free Offers to PlayStation Plus Subscribers
Mushroom Wars
2Xtreme
VEMPIRES - minis

Discount Offers to PlayStation Plus Subscribers
Soldner-X2: Final Prototype - 30% Off (PlayStation Plus price $9.09, regular price $12.99)
Soldner-X: Himmelstrummer & Soldner-X2: Final Prototype Bundle (PlayStation Plus price $10.79, regular price $17.99)