From UVaToday:

"If anything bothers University of Virginia physicist Lou Bloomfield, it's a wobbly table. So much so that he actually invented a material to eliminate the problem. The material, a type of silicone rubber that is both rigid and fluid – a "viscoelastic" solid – can be placed under a table leg where it conforms to the shape of the leg bottom and the floor surface, perfectly filling the gap.

It turns out, the material can do a lot more than that."

For the full story, see:
http://news.virginia.edu/content/uva-physicist-bloomfield-develops-new-silicone-rubber