• JDiskReport (Windows)
  DiskReport enables you to understand how much space the files and directories consume on your disk drives, and it helps you find obsolete files and folders.
• Disk Inventory X (Mac)
  Disk Inventory X, disk usage utility for Mac OS X

Sources

• JDiskReport: l’analyse de votre espace-disque sous forme graphique – Infobulles.ch
• JDiskReport – Le blog de libellules.ch
• Visualiser l’espace de votre disque dur – Toile-filante