Many SysAdmins (and regular users), certainly any who work on a system used for everyday computing, need to periodically perform maintenance on the filesystem and disks. Here are a few scripts that I have found useful.
Finding Duplicate Files
There are a few scripts for this task, most of which calculate a database of the MD5 sum of the file, and compare this with other files. Warning: calculation of an MD5 sum takes a bit of time. If you're operating on GBs of files, these scripts may be best run overnight...