Using the New Keyboard Maestro File Action
Remember my homebrew macro for prepending a file with the current time stamp? Here's the old version with all of the shell scripting:

Here's the new version using the newly released Keyboard Maestro 5.2:

Here's a bonus for quickly putting the path of the currently selected files on the clipboard.

These macros will work on multiple selections too. A big update to Keyboard Maestro.