The game I get the most mileage out of these days is the 1978 edition of Tunnels & Trolls, the classic sword and sorcery game by Ken St. Andre, edited by Liz Danforth. It’s super easy to run at the drop of a hat. The print editions of T&T are currently sold out! Flying Buffalo, the game’s original publisher, is planning a “Deluxe Edition” of the game, authored by Ken St. Andre himself.
Until that appears, you can download the free starter rules here, or read the abridged game rules online. If you yearn for ink on paper, Flying Buffalo sells pocket-sized two-in-one solo adventures that include the core rules: Look for the heading “Pocket-book sized double solo adventures”.
I play Risus: The Anything RPG, Marvel Heroic, and Old School Hack any chance I get, and I also enjoy Trollbabe and Sorcerer by Ron Edwards. There is a deluge of other games I sometimes play, and even more that I’d like to try, but that’s a snapshot of what I usually write about here.