A lot of GMs advise rolling behind a screen, so you can fudge rolls when you get a result which would be bad for the story. I think that at best fudging is unnecessary, and can be remedied by being more thoughtful about what rolls you ask for (and I go in to how I think about rolls), and at worst cheating, where you’re explicitly ignoring the rules of the game.
This is a starter adventure I wrote and ran for my Troika! group. It’s in two parts: first you have to get to the manse, by travelling through Emmy Allen’s Gardens of Ynn, then you have to search the manse for the magical artefact the party’s patron has sent them to find. Don’t worry, Mazirian is supposed to be long dead… but is he?
Today I ran my first session of Troika!, a very weird Book of the New Sun / Dying Earth / Discworld style game. We had a lot of fun, it’s pretty rules light, and we’ll probably be playing it again some time.
Knock! is a recently kickstarted zine full of goodness from the OSR blogosphere. It’s wonderfully designed, and crammed with information. There’s a nice mix of stuff which is immediately useful (like Just Use Bears, or the Dungeon Checklist), and some more thought-provoking articles too. Plus some great art. I recommend it, and am looking forward to issue #2!
Call of Cthulhu uses a roll-under percentile dice system. It also has a notion of task difficulty and situational modifiers, and a way for two characters to directly compete. This post runs through all these variations, with lots of graphs, and gives my rules for deciding what sort of roll to make when.