This afternoon I had just finished sandwiching a table runner together. The backing length needed to be cut off a little. Went over to my cutting table to make a quick swipe.........Didn't realize the sewing machine cord was under another fabric. I took my rotary cutter and ruler and went zip.....sparks flew, big poof and then smoke. Melted a section of the cutting mat and a little piece of batting. You should see the chunk melted out of the cutting blade. A couple of black spots in the cotton. I didn't receive a shock but am quite surprized it didn't trip a circuit breaker. Just nicked the machine cord. I can get my husband to replace the cord but you can be certain I'm gonna get a lecture. Yikes! I feel l stupid but very lucky.