Following up on Leo's post, a quick update on QAP : Since this thread was created in 2014, Folders Popup became Quick Access Popup and has been constantly updated. As of July 2020, it is at v10.5.2. You can download it for free on www.QuickAccessPopup.com or get support on forum.quickaccesspopup.com.
And for specific info about DOpus and QAP, see:
https://www.quickaccesspopup.com/tag/directory-opus/
Jean