Kitty From Video-angels Megaupload What Can I Do To Help Prevent My Cats From Tracking Kitty Litter Everywhere And Making A Nasty Mess?

What can I do to help prevent my cats from tracking kitty litter everywhere and making a nasty mess? - kitty from video-angels megaupload

I put a towel in front of the box, but did not catch much. They have cat litter on the floor, and I hate to go. All ideas, what you do to control the cat litter for everyone?