Piece of fleece over the wood pellets. The fleece muffle the noise and create a softer surface, while wicking urine through the very absorbent pellets. Twice a day, I simply roll up the fleece, take it outside, shake off the poops and hay, and lay it back down all nice and clean. The cage is completely odor-free, even though I haven't changed the wood pellets for a full 3 weeks.
i wasn't aware that guinea pigs like stuffed animals. i'll have to put one in the new cage ... YES! They love them .. use them as pillows :).......my piggies love them. We wash them along with their beds each week.