Here are some relevant links (I'm sure there will be other systems that have been recreated in FPGA form):
http://www.retrocollect.com/News/super-nintendo-recreated-in...
http://hackaday.com/2013/01/23/stuffing-an-nes-into-an-fpga/
http://www.sega-16.com/forum/showthread.php?12847-fpgagen-a-...
http://www.fpgaarcade.com/platforms/
https://en.wikipedia.org/wiki/1chipMSX