People have come up with other, you know, more exotic ideas, looking for glitches in reality, sort of like in The Matrix when the black cat walks by twice. Remember that scene with Neo? So, looking for mistakes. I don't buy that at all because a very clever error-correcting simulation could simply wipe clean the memory of any such glitch after correcting it. But for me personally, if we could actually see the kinds of simulations that would be required, if we could build them, then I'd start to really take the idea more seriously.