Insync is a feature rich Google Drive client for Windows, Mac and Linux. The ability to sync and manage Google Drive files for multiple accounts and automatically convert files to Microsoft Office or OpenDocument are fantastic and make Insync perhaps the best Google Drive desktop client available today. Certainly worth the one time payment for those features alone. The added feature of it supporting OneDrive in the near future will make it worth looking into when it is added.
$29.99 15 day free trial available. Visit Site
StableBit CloudDrive
StableBit CloudDrive
StableBit CloudDrive creates a virtual hard drive that acts and behaves like a real physical hard drive. The cloud drive can be located on one of several cloud storage providers or on a local drive giving you the benefit of trust no one encryption on a local drive. Currently supports
  • Amazon S3
  • Box
  • Dropbox
  • File Share
  • FTP
  • Google Cloud Storage
  • Google Drive
  • Local Disk
  • Microsoft Azure Storage
  • OneDrive
  • OneDrive for Business
not rated $39.95 30 day free trial. Visit Site