This is one of those tips a handful of people will find useful but is worth sharing nonetheless. Those who use OS X on server computers might find it particularly useful.
The following command will cause any new archives (zip files) you create to automatically have the 24-hour time appended to the filename. For example, creating an archive from the folder Pictures at 2:13 p.m. will result in an archive with the filename Pictures 14.13.27.zip (with the last two digits representing the second count).
To activate this feature, open a Terminal window (open Finder, select the Applications list, and then in the list of applications double-click Terminal within the Utilities folder), and type the following:
defaults write com.apple.finder ArchiveTimestamp -bool TRUE;killall Finder
To deactivate it at a future date, type the following into a Terminal window:
defaults delete com.apple.finder ArchiveTimestamp;killall Finder
