Is there anything you can do on a rented QC that you can't do cheaper on a simulated QC on a "classical" CPU/GPU today?

there's still a long road to commercial applications but today's hardware is simulating quantum systems beyond the scale of classical methods, for example [1]; an interesting line of work opposite to this can be found in those who improve classical methods towards such examples [2], but these are only developed because of the existing quantum hardware

Really though, today's IBM hardware is good fun to play with, eg for generating moderately large GHZ states

[1] https://arxiv.org/abs/2510.26845 [2]https://arxiv.org/abs/2306.14887