Roll for Shoes

Taken from

The system
The minisystem goes like this:
 * Say what you do and roll a number of d6s.
 * If the sum of your roll is  higher  than the opposing roll (either another player or the DM), the thing you wanted to happen, happens.
 * The number of the d6s you roll is determined by the  level of skill  you have.
 * At start, you have only one skill:  Do anything 1.
 * If you roll  all sixes on your roll, you can get new skill  one level higher  than the one you used for the action. The skill must be a subset of what happened to you in the action (Say, Athletics 2 if you were climbing a wall, or Teeth of Biting 2 if you were eating a cake).
 * For  every roll you fail, you get 1 XP.
 * XP can be used to change a die into a 6 for advancement purposes but not for success purposes.

Examples
This mini-system works beautifully for crafting characters on the go. Here are some example "charsheets" from the dungeoncrawl of Cakewalk that I ran: But my favorite moment was this:
 * Krey the Heretic Monk of the Church of Pain : 0 XP Do anything 1, Fist O'Pain 2, Burning Fist O'Pain 3, Heretic 2, Teeth of Biting 2!
 * Ferret the Son of a Shoemaker: 2 XP Do Anything 1. Boots of Kicking 2. Feet of Feats 3. Supplier 2.
 * Ryu the Polymorphed Egglayer: 2 XP, Reptillian 2

I had asked the players if they were doing anything to prepare for the dungeon before leaving town. One of them said he's checking to see if "he has his heirloom shield" with him. He rolls and botches, and so I say: "Your father is a shoemaker. You are not sure why you ever thought you had anything even remotelly close to a shield." After a little while, this character and the would-be monk make it to the heavy doors of dungeon Cakewalk and have a little conversation regarding their preparedness. The monk says he's barefoot and happy to be so, 'cause, well, he's a monk! And then the shoemaker says "I check to see if I have shoes on!"... Which is beautiful, of course - we've already established he's the son of a shoemaker, so he definitelly has shoes on. So if he  does  win this roll, we know that he doesn't just have shoes on, he has awesome shoes on!

And then he rolls a 6 on that roll and gets Boots of Kicking 2.

And then he rolls a 3-6 roll for kicking down the dungeon door, and upgrades it into Feet of Feats 3.