I've been using the Hofftari feet for all my printers, but on some prints it tends to wiggle some, got an idea to try squash balls for vibration damping, since they are made of a rubber used at industrial vibration damping applications.
When the printer is placed on the feet it almost feels like its standing on jelly, but while printing, even quick movements its almost completely still, way better than the hofftari feet at least.
There are different hardness of squash balls, so use the model matching your printer. For the Prusa i3 MK2 I'm using the Yellow two dotted balls which are pretty soft. The cup itself are designed for the ball to be compressed around 30%
This could also be used for HiFi electronics etc as well of course.