How do I cut 1/2" rubber mats?

[rob love]

Best thing I have found for cutting rubber is a straight edge and razor knife. That is assuming it does not have the little pieces of steel belting in them. Cut once, bend it a bit, cut again, and repeat until it is done. And of course, use a brand new razor blade.
Anything like a saw or grinder disc is going to make an incredible amount of dust or clog up as the heat turns the rubber to goo. Perhaps running water on the cut like you would with cement might help.