Easysync allows you to synchronize files among different computers. You pick up a directory you want to synchronize and Easysync will perform synchronisation whenever this directory is changed. The server part propagates the sync signal among clients, so that if there is a change on one client, all other clients will perform synchronization. It is based on Unison.
QT Cloud Drive is a cross-platform desktop application for connecting to Amazon Cloud Drive. It can be more convenient than using Web-based access because it allows you to remain constantly signed in and allows you to drag and drop files between the cloud drive and other desktop applications.