I wanna introduce you guys to
Receiver:
It was made in 7 days for a contest, and costs $5 on Steam. The graphics aren't exactly great, most of the physical objects are missing textures, and there are only 2 mobs in the game (amounts to flying tazer drone and stationary turret), but for those 2 mobs it has a detailed damage model, the game is procedurally generated and random each time you play, and it has the most detailed gun physics I've seen in a game.
In particular, instead of just press R to reload, you'd need to go through the steps to reload. Say you have an empty gun, a box magazine and a handful of bullets. You'd need to put the bullets into the magazine, put the magazine into the gun, and pull back the slide to chamber the first round. Sounds tedious, but it can lead to some real nail-biting situations.
Example from when I was playing yesterday, the game randomly gave me a Smith and Wesson Model 10 revolver. I was playing peekaboo with a sentry gun, trying to hit it in either the battery or the camera, and just as I got it taken down, I hear the beep of a flying drone zooming at my face. I'm frantically backing up and dodging while I'm opening the cylinder and hammering the extractor. 2 casings are stuck in the cylinder and WILL. NOT. EXTRACT. I went ahead and loaded the rest of the chambers, gave the cylinder a spin to give me a random chance to get one of the good chambers, point at the drone just a second to spare-
*click*
Yeah, I got killed, but it was a lot more visceral than if I'd have just hit R, watch my guy dance, then pull the trigger, knowing the weapon would fire. Something about actually going through the steps for reloading instead of pressing a key and having the gun reload itself is rewarding in a way that's tough to describe.
The way that the various rooms, enemies, and items are randomized also adds a challenge all its own. A few rooms in, you might find you have a Glock with 5 magazines full of spare ammo, or that you have a 1911 with one round in the chamber, and 5 flashlights. I'd almost describe it as a Roguelike FPS if it weren't for the fact that everyone who plays Roguelikes would hunt me for my pelt.
At any rate, I found it was surprisingly fun, and I like to share fun things.