Saut is a one-button platformer where that one button makes you jump. Unlike Canabalt or Dino Run, your avatar doesn't run automatically. When you jump, you leap forward and slide upon landing, making your way from left to right in a series of bunnyhops. Tap the spacebar for little hops; hold it down for longer leaps.
And that's it, sounds simple enough. Except it's fantastically difficult. If you can play it your entire lunch break without wanting to top yourself - or me, or perhaps the game's designer - then I congratulate you.