They say Macs don't fill up with crud over time due to the lack of the "design flaw" that is the Windows Registry. This, in my experience, at least, is simply not true... mind you, my Mac wasn't running slowly or anything like that. It was, however, clogged up with old demos and other software I downloaded but haven't used again... that is, until I backed up my system (you know, just in case anything went horribly wrong), wiped it clean, reinstalled Mac OS X, applied all the updates, and reinstalled (and reactivated) the applications I actually wanted to keep using. To some extent, this cleanup was prompted by a forum user (I don't remember the name) who had a link in their signature called "Programs you should never use". I had some programs and frameworks on that site's "bad list", which are now gone Anyone else done something like this to their Mac?