best way to save my wood floor


What is the best way to protect my wood floor from the speaker spikes. I have been using the sound anchor coasters. They are great, but too high off the ground. I have also used pennies, but they are too soft and spike can still get through.
what is thin and sound good? Thanks in advance.
flying
Check out: http://www.audiopoints.com/apcd2.html they make a coupling disk that works extreamly well. I use them on my hard wood floor.
I put thin strips of felt on one side of a 1/4" wooden board, put that face down on the hardwood floor, and put the speakers on top of the board (with spikes).