I can still play these games today, but just don't have the time:
- Dangerous Dave, John Romero's first "popular" game, predating Keen/Wolf/Doom. Three decades later, and I still haven't managed to beat this game (without using cheats or save states that is).
- Bio Menace, An action platformer by Apogee, made using the same engine as Keen. You are Snake Logan, a CIA operative who needs to save Metro City, which has been invaded by mutants. A very fun game with good controls and smooth movements.
- The Skunny series, A bunch of platformers featuring Skunny the squirrel, made by Copysoft. Save our Pizzas in particular was pretty memorable, where Skunny travels back in time to ancient Rome because an evil chef wants to destroy the invention of pizza so that he can make his own imitation. Very whacky and cartoony, kid me loved this game.
- SkyRoads, A fun space runner. Think Temple Run, except you're in a spaceship that's... not flying and is on a road, in space, and it can also hop! In hindsight, it sounds weird, but trust me, it's fun.