Great Games for Low-End Rigs?

Game Dev Tycoon, Final Fantasy VII, Fallout Collection, Metal Drift, almost everything else previously mentioned.

Killing Floor. I've played the hell out of it.
Also, you might consider Max Payne 1,2; Binding of Isaac, etc.

Diablo 2, Starcraft, Shank 1 and 2, Killing Floor, Halo, Left4Dead 2, Borderlands, Mass Effect
-From left to right the requirements generally start getting higher. All of which I can run on my "non-gaming laptop" ($400 a couple years ago)

The suggestions I usually give: Deus Ex and System Shock 2.

portal 1
portal 2
audiosurf
killingfloor
microvolts

These are all games i played on a laptop with an Intel Core 2 Duo at almost 3ghz, with an intel HD 3000 graphics, and 4gb of ram before i got my gaming one lol

NOWWWW games i would assume would work are below.

Stanley Perable - based on source, not very graphically overdone. quirky and the commentary is funny.
AudioSurf 2 - i meannn... it's audio surf graphically. least seems it to me xD!

But thats just based on replay value xD! none of these were at 60fps or high settings mind you >..>

Big Rigs.

Mount and Blade:Warband

Crysis 2. I am serious. I know low-spec, because I play on an E-450, and Crysis 2 is by far the most graphically impressive game I have ever played on this thing. Wrench up the lowest setting at the lowest resolution, and disable DOF through cfg, and then you get a really nice thing at roughly 16FPS, which is actually quite playable. I am serious. I get about the same number of frames on Crysis low setting, and it looks much worse than Crysis 2.
Walking Dead also plays nicely, and apparently Bioshock works on any average PC/laptop on this decade.

you've come to the right place, friend...my system is HORRIBLE...so heres a list of things i play that are great:

Risk of Rain
King Arthur's Gold
Torchlight
Waking Wars
A Valley Without Wind
Altitude
Clutch
Dark Messiah of Might & Magic
Crayon Physics Deluxe
Eldritch
Enclave
Eufloria
Rune Classic
Favble - The Lost Chapters
Flatout
Gunpoint
Knytt Underground
Night Sky
Lord of the Rings Online
Pinball FX2
Satazius
Slam Bolt Scrappers
Solar 2
Stealth Bastard Deluxe
Syder Arcade
Worms Crazy Golf

theres a lot more too, but thats enough to keep you occupied...

Dead Pixels,DLC Quest run fine.

you should say what kind of games do you like. if you like roguelike game, try : sword of the stars the pit

I have no idea why Serious Sam 3 works fine on my craptop.

Battlefield 4 totally!

Shatterd Horizon.