I can confirm that Nexus Media Importer by Homeysoft worked with a generic USB OTG cable and a couple of USB drives I had sitting around. I don't know if there is a free alternative but this one seemed to work.
EDIT: Just to clarify the Nexus Media Importer worked with my Nexus 10. I had not seen a confirmation against the actual N10 so figured I would confirm.
Last edited by JanetPanic; 16th November 2012 at 06:55 PM.