There are 42 in the list, and it seems like new entries in the 'Mac cleaner' market space pop up every day, metastasizing like a cancer. (I did a search for 'cleaner'.) If MacUpdate will let me, I intend to post this every time a new or updated version of one of these things shows up on this site. As a public service to the MacUpdate community, I've found as many of these 'cleaner' apps on this website as I could and listed them them below. This is not a review per se, it is a discussion of the class of software to which this program belongs.