For video games, Ostranauts. It's the perfect space survival sim IMO. You wake up on an industrial salvage station and get a ship. Then you fly to derelict ships and scrap them for money and parts. Build up your own ship and travel farther and farther out. It's jank as fuck to learn but once you get it down it's the type of game where you put on music then just go for hours and hours. It's early access and a lot is changing but the core gameplay loop is so addicting already.
For tabletop games, Infinity. It's the best miniatures skirmish game I've ever played. The rules are deep but tight. The number of minis you put on the table is just right to me. List building is the best of any game I ever played. The rules are free. The app is free. The miniatures are the best out of any wargame I've ever played. It's just a shame that people are so locked into Games Workshop that they don't see other games as an option. Like I had a couple friends get hardcore into it but never more than that. And at the height of it's popularity at our store we had one of the best players on the East coast play in a tournament. That was a sight to behold. Like I'm not a tourney player at all for any game. Watching the number 1 east coast player do his thing was the most inspired I ever was to become a tournament player.