you know i can't help but think that the fear of static damage to components is overly exaggerated or not i mean it also got me to think twice even though i used to care less before and nothing happened but then again we can never be too careful.
So i'l take your advice and from now on only put my components on a wooden table or the tile floor ^_^
Its unlikely simply because to cause damage you almost have to make direct content with an IC pin. And they are usually covered and a very small part of the surface area, you're almost always touching the non-conductive PCB, and you're constantly touching big chunks of metal to discharge it while building and really shouldn't be moving much.
Its also not really what you lay it on, YOU have to build up a charge. I've built a dozen on carpet floors, although I almost always lay the parts on their boxes or bags if I set them down. if you have a wrist strap, or ground yourself you're fine. And I completely agree with bigcyco. For 5 bucks why risk it. It CAN happen. The probability is just really low for building a PC. Handling ICs is a whole different story