Eureka! A chair mat.
While vacuuming yesterday,I noticed that I have a leaky office chair. I don't know if it was some kind of hydraulic fluid or grease or what. In looking around for something to put under my chair, I came up empty in my search until I remembered....
I have an old, no, very very old Dritz cutting mat that I bought used at a yard sale back in 1994. I was a beginning quilter, so was delighted when I found a used one at a yard sale for $5. I later learned that this particular mat was not self healing. It soon became rather unusable and dulled my blades quickly. Why I kept that thing all these years, I don't know. But today, I was sure glad I did. Measuring at 30 x 36", it was perfect to fit under my chair's leg span. Woo hoo!! I am doin' the happy dance.