Not car tinkering, but more a surface for it (and me) to sit on,
Used some 5mm coin rubber flooring, It came on 3 rolls
Its really heavy too.
I scraped the old paint off the floor and glued it down:
and black silicon sealed all the edges
the rubber smell is fading now,
I have some thin pieces of ply to use under the trolley jack, the axle stands and the tilting lift, so it doesn't damage the surface
It is insulation from the cold concrete, and is comfortably cushioned enough to kneel on too,
Cleans easy with the small leaf blower, then just a wipe with quick detailer on the sponge mop..
Well pleased.