|Use "cheap", soft mouse pads, the kind with a colored lycra on one side, and spongy foam on the other, about 1/4" thick, underneath your sewing machine/serger. I have two side by side underneath my sewing machine.
You can stick pins/needles into the pads without fear; scissors and other things won't roll off; and machines won't skitter or vibrate anymore!
In addition, I used an old wrist rest -- like the mouse pad above, but about an inch thick, 3" wide and 12" long -- under just the back of my machine to tilt it forward. This helps a lot to reduce neck strain and eyestrain. The combo of wrist rest/mouse pads is great - no slipping. No marks on the table, either.
When I lived upstairs in an apartment with wood floors, I cut two mousepads in half and put the halves underneath the legs of my sewing table to cut down the noise of the sewing machine for my downstairs neighbor!
These pads are commonly available for about $2 each, or frequently give-aways with company logos printed on. *Don't* use the ones with the hard surface.
(If you really are interested, a stack of 3 pads makes a great base for tooling designs in copper! Supportive, resilient and easy to manage. )