Nostalgic prime number generator
Perl, 80 78 71 bytes
-9 bytes thanks to @Dada
$_++;`lscpu`=~/z:\s+(\d+)/,sleep$1,(1x$_)!~/^(11+?)\1+$/&amp;&amp;say while$_++

Runs the command lscpu and finds the CPU speed in MHz.  The faster the CPU, the more time it sleeps between outputs, 1 second for every 1 MHz.  Runs on Ubuntu 14.04.5.  On my particular machine, this tests each number every 800 seconds (13 minutes, 20 seconds).  On faster machines, this can be over 50 minutes.  Change it to sleep$a/400 to get something much more sane for testing purposes.