I play, almost exclusively, non-AAA games. Some gems, known and hidden:

• Autonauts and Autonauts Vs Piratebots - Cute automation games
• Spelunky - Elegantly simple and well executed platformer
• BPM: Bullets Per Minute - Rhythm FPS. Others have tried. None I have found have been as good.
• Immortal Redneck - FPS roguelite
• Ziggurat - FPS Roguelite
• Receiver II - Unique FPS roguelike. Every part of everything that moves is simulated. The hammer on your gun hits a firing pin which hits the primer on the cartridge. You can get stovepipes, misfires, double feeds, etc. You don't reload by hitting 'reload' but go through the full manual of arms in a shooter where the tolerances for failure are fairly slim.
• Valley - running game. The feeling of letting a hill propel your running to otherwise impossible speeds, bottled. Nice little story too.
• Dredge - Lovecraftian fishing game.
• Tunnet - lovecraftian network technician simulator. Build a network to allow communication between computers in an underground society with unspeakable horrors occasionally destroying your mind/body.
• Opus Magnum - Programming puzzles
• Vagante - roguelike with tight tolerances
• Ruiner - Cyberpunk slash n dash with a soundtrack half by Sidewalks and Skeletons. Very fun.
• Tails Noir - Detective story. Normally find the anthro thing a bit tiresome but this was pretty good. Well written.
• Elderborn - First person brawler
• Webbed - be a peacock spider. Rescue your lady spider. Help insects. Fight a bird. Dance.
• A Story About My Uncle - Movement game. Jump, dash, grapnel. Simple and elegant.
• Tormentor X Punisher - Top down twin stick shooter. Everything dies in one hit. All the enemies, and you.
• Tin Can - Survival game in which you try to keep up an escape pod long enough to be rescued, which is hard when it seems to have been made by the lowest bidder's lowest bidding subcontractor and maintained with all the loving care of a convenience store bathroom.