FolderSync is a application that enables simple sync to cloud based storage to and from local folders on the device memory card. It currently support multiple SkyDrive, Copy.com, Dropbox, Dump Truck, SugarSync, Bitcasa, Ubuntu One, Box.net, LiveDrive, HiDrive, Google Docs, NetDocuments, Amazon S3, FTP, FTPS, SFTP, WebDAV or windows share (Samba/CIFS) accounts, and support for more platforms are planned. Read-only access to protected file-system also supported - requires root.
Effortlessly sync your files. Backup your music, pictures and other important files from the phone to your cloud storage or the other way around. It has never been easier. Tasker / locale support enables fine grained control of your syncs.
FolderSync also contains a full file manager, that enables you to manage your files locally and in the cloud. Copy, move and delete your files in your cloud/remote accounts. Support for creation/deletion of buckets in Amazon S3. Upload and download files from the phone. It's all supported.
There is also a lite version, so you can test functionality before you buy. The lite version only allows two accounts and has no sync filters or Tasker support.