If you can determine the angle, perhaps a Hexagon-Shaped-Rug ? Or, someone else posted of how they used a yoga mat as rug pad, perhaps you could trim one to fit? You don't really need a mat right in front of the dishwasher, but rather alongside it. When the door is open for loading, it covers the mat you have now anyway.

I would buy an inexpensive rubber-backed rug, probably an 8 foot runner, and cut it across the center. Then trim the cut ends on an angle, to match the counter angle, and duct tape it together on the bottom. Or, you could get Flor tiles to make the rug, and cut them to fit the angle.

Thank you both. Might look into that floor/carpet tile idea, or see about cutting/mocking something up.

Carpet places will cut and bind a piece of carpeting to your specifications. Make a template out of cardboard, and take it to a rug store. That way you'll get exactly what you want. The duct tape idea might work for a while, but I worry that duct tape adhesive will end up on the floor, or that at some point the two pieces will separate. The rug store solution is more permanent. I brought an old piece of carpet I had in my attic to a rug store, and they cut it and fitted it to a very strange spot I had by my back door. They charged very little to do it, like a few dollars per foot. I was buying another piece of carpeting from them, though.

Thanks leavemeout. Maybe I could find a remnant, I do have a carpet place. Thanks for the idea!