Dropbox
Dropbox is an online file synchronisation service
Google Drive
Google Drive is an online file synchronisation service
Microsoft OneDrive (SkyDrive)
MIcrosoft One Drive (formerly SkyDrive) is an online file synchronisation service
Oracle VirtualBox
VirtualBox is a free Open Source Software virtualization product that runs under Windows, Mac, Linux or Solaris, and lets you run multiple operating systems (inside multiple virtual machines) at the same time