Try-out page
Captcha lab
Four home-made puzzles, candidates for the check before a first message without an account. Each one is real: the puzzle comes from the server, and the server decides whether your answer counts. Try them and pick.
Idea 1
Guide the hummingbird
Drag the bird through the gap to the flower. Touching a side sends it back.
What the server checks: The server replays your movement: inside the gap all the way, no jumps, and not too quick or too even to be a hand.
Idea 7
Invisible work
Nothing to do. Your browser solves a computing task by itself. In real use you would not see this at all.
What the server checks: One hash on the server proves the work was done. The task doubles in size, again and again, for an address that keeps asking.
Idea 9
Trace the flight
Draw over the dotted line in one stroke, from the filled dot to the ring or the other way.
What the server checks: The server scores how much of your stroke is on the line and how much of the line you covered, plus the same hand checks as puzzle 1.
Idea 10
Tap the rhythm
Play the beeps, then tap the same rhythm on the big button or with the space bar.
What the server checks: The rhythm is sent as sound, not as numbers. The server compares the gaps between your taps, at whatever speed you tap.