yesterday i did a search for "plastic bags" because we have millions of them.
it occurs to me that some of the straw placemats we had when i was a kid were a bit like the plastic bag crochet fabric of this bag
http://www.craftster.org/yabbse/index.php?board=76;action=display;threadid=2871;start=0you could quite easily make a double crochet (US: single crochet) circle of whatever size you like, to make coasters, placemats, i guess doormats too.
it's recycling, and if they got too mucky you could just do new ones - if you are anything like me you have an unlimited supply of shopping bags.
if you can't crochet, i assure you it is very simple to learn.