Up above are the little coffee tables I built for the photography studio I rent out. The tabletops are white melamine from Ikea. Alas, as of late the renters have been thoughtfully using the tabletops as a cutting mat:
My first thought was to replace the tabletops, but a) Ikea has discontinued the square ones, b) even if they didn't, it's wasteful to throw those out just because the surface is ruined and c) even if I replace them, someone is bound to repeat this thoughtless act down the line and ruin another pair.
It makes sense to resurface the tables with self-healing cutting mats, but the largest size my local art store carries is the common 24x36. Then someone pointed me towards DraftingSteals.com, an online retailer that sells big-ass cutting mats (and judging by the photo, has been since 1979):
A bit too expensive for me, but nice to know where I can buy huge cutting mats, for future reference. What's in the picture is the 4-feet by 8-feet, which goes for 245 bucks, or $239 if you don't want the grid printed on it. The 4x6 is a more manageable $90. But their big-daddy mat is the 6-foot by 12-foot, which comes in at a whopping $325.80, and since it doesn't roll up I'm guessing the shipping ain't cheap.
They also sell these Safety Rulers, a metal extrusion with a guard built in for klutzes, up to 100" in length. I haven't needed to use one of these...yet. (Fingers crossed.)