My command and project have big experience in developing benchmarks with anticheat protection.
For example CUDA Factorial Benchmark - http://www.xtremesystems.org/forums/showthread.php?t=233280 or TOC F@H Bench - http://total-oc.ru/download.php?id=52 (page in Russian)
We can modify one f them for HWBot.org or make new benchmark on pi\prime algorithms I can discuss about any variants, you can send me PM or always find me on ur forum - http://total-oc.ru/forum/viewforum.php?f=58 (this is english threads)