I found one of these mops out for trash- they use disposable sponge type things (not a swiffer, but like one) and people generally abandon them when they see the sponge refill costs nearly the same as a new one.
So I decided to make a reusable, washable dusting head using scrap yarn. There are a lot of patterns on Ravelry ("swiffer cover") but after some trial and error I decided to tweak the ball band washcloth pattern from Mason Dixon Knitting, which i think makes a superb fabric for how I use the mop (only light dust and dog hair pickup between heavy cleanings with a mop and
bucket). Free download
here at Ravelry!. Note that for this size, using just general worsted weight, I used 65 stitches across and repeated the band pattern for a total of 6 bands, then sewed it to make two pockets so it fits on the head.
I'm making a few new heads out of scrap yarn and figured I'd document in case anyone else has one of these hanging around.
First picture illustrates why I need to spend so much time and effort on keeping my floor clean.