If you find yourself itching to play a retro FPS on your modern machine, give DUSK [0] a try.
The style is on point. This game is ugly where it counts, the environments are blocky and grotesque. The guns have satisfying sounds and animations, the enemies are numerous and the bosses are fun. This game really makes me feel like I'm a kid playing video games instead of last classes of school.
I'm waiting for HROT [1] to be released. It's supposed to be similar to DUSK, but set in Czechoslovakia. The screenshots are very promising...