The key is to link up observer with the experiment outcomes so you can only observe unlikely possibilities (and be dead in the rest).

Understood, but you could also set up an apparatus that simply observes a large region for a long period of time without killing anyone, watching for highly improbable events. Since each observer also lives their total lifespan, you get a much higher probability of a given observer observing a succession of improbable occurences.

Just create a machine that reads bits from a random data source and stops forever upon reading a 0 bit. Will the device run forever in some universe?

If you built the device, and it didn't run forever, what could you learn from this? Nothing, except maybe how to build cool counting machines. :)

That what reporters are for :) If you read the news you will see an endless stream of highly unusual events, but unfortunately that doesn't prove anything.

Touche. :) But in the same vein, what would a series of failed suicide attempts prove that the mentioned apparatus could not?

Any machine that you build will produce expected results, up to 10^-15 precision with current hardware.

Failed suicide attempt is unlikely and provides evidence towards many worlds as a theory and not just interpretation.

Sorry, by apparatus I mean any method of observing a large body of matter or space that exhibit quantum behaviour (i.e. anything), not necessarily a physical machine. We are just looking for a series of highly improbable quantum state transitions.

Doesn't matter, any method of observation you choose will produce expected results.

Unless you observe yourself, where you will not be able to observe expected results because you're dead.

Think of each observer attempting to push a rock into their palm and having it appear on the other side, without enough force to push it through. Think of everyone on the planet attempting this simultaneously, thousands of times. If the rock disappears and reappears on the other side for one observer, doesn't this accomplish the same thing, at least for that observer, that the suicide attempt does?