If you trade a USB thumb drive, hard drive or other portable storage between Mac and Windows systems, the .DS_Store, .Trashes, and other starts-with-a-dot files left behind by Macs can get annoying. This script automatically wipes away those left-behind files.
Image via WeLoveMac.net.
MacWorld's OS X Hints section suggests modifying the default umount script, such that it automatically searches out and wipes away any traces of Mac-only functionality from drives when they're ejected or unmounted from the system. It takes a small bit of Terminal work, but the results could pay off long after your work is done. Two catches, though: updating your system to a new OS version may wipe this change away, and if you actually want other types of hidden files (named with a period as their first character), this script will automatically wipe those, too. Still, both are pretty niche concerns, compared with the annoyance some may find with unwanted files cluttering their drives.