..like the ones in The Matri, who allowed its denizens to evolve to knowledge of virtual reality, rather than keeping them at a medieval level, or using the bio-energy of sheep...
But I am more interested in the epistemic mistake people keep making. People keep assuming that it is possible for simulatees to know what is going on outside the simulation (or, equivalently, that basic laws must be same).
If it is... I hope they do not crash the system with the test.
http://www.huffingtonpost.co.uk/2012/12/12/physicists-universe-simulation-test-university-of-washington-matrix_n_2282745.html
Be sure to check out the actual reseach papers linked in the article! I would have linked to them directly, but the article is full of follow-on links of considerable interest.