I had hoped at least one of our cats would do that with ours (we have the Neato, not the Roomba, but same thing, basically) but they all ignore it. (The fat cat Millie goes running.)
that is too funny. Cats do look for any available clothing spot to hang out in/at. I can put a pair of shorts on the bed and go to the closet to get a shirt to go with it, and come back out 30 secs later and a cat is already sleeping on the shorts.