If you mean defragment a hard drive, then there's no real need to do so. OS X defrags all files under 20 MBs on the fly. Furthermore, OS X's filesystem minimizes the effects of fragmentation, and today's hard drives are much faster so there's little loss in performance caused by fragmentation until the drive becomes nearly filled. At that point, however, fragmentation would be the least of your concern.
If you mean defragment a hard drive, then there's no real need to do so. OS X defrags all files under 20 MBs on the fly. Furthermore, OS X's filesystem minimizes the effects of fragmentation, and today's hard drives are much faster so there's little loss in performance caused by fragmentation until the drive becomes nearly filled. At that point, however, fragmentation would be the least of your concern.
On a pc, there is an application called "disk clean up" which checks for unused temporary files, temporary internet files, broken links, etc. Is there anything comparable on a Mac?
I think it is possible that those unix scripts don't get run on a computer that is not left on all the time. MacJanitor is a shareware app that lets you run that stuff whenever you care to.
Peter.