AEM watching external hotfolder

Hi 

As correctly mentioned by Jorg, you can listen a folder and when there is change in it, launch the workflow.

Adding a reference article covering "Listening a workflow event ":

Link:-http://blogs.adobe.com/experiencedelivers/experience-management/event_handling_incq/

Option 2:

You can create a custom component/Service to monitor local file system directory, and you can trigger anything in it when there is a event for change in folder.

Reference link to the library(java.nio.file) :- http://www.codejava.net/java-se/file-io/file-change-notification-example-with-watch-service-api

                                                               http://www.rgagnon.com/javadetails/java-0617.html

                                                               // jpoller, JNotify etc 

PS: Option 1 would be my preference among these two options.

Thanks and Regards

Kautuk Sahni