When I started adding Services to my apps (Find Any File, iClip), I realized that this was not enough for users who want to write workflows with Automator or Applescript because there seems to be no way to invoke Services from Automator nor AppleScript.
So I wrote an Automator Action that allows you to run any Service that operates on Text or Files & Folders:
Find instructions and the downloads on github (including Xcode source).
License is unrestricted, i.e. totally free.