Another excellent utility for backing up important files, or keeping a portable drive in sync with your desktop PC is GoodSync.

Does exactly what the name implies. Backup and synchronization of your important files.

GoodSync is an easy, secure, and reliable way to compare, synchronize, and backup your business documents, emails, contacts, photos, MP3s, and other important files. GoodSync synchronizes files between desktops, laptops, and external drives, and works over a network or the Internet.

• Robust, Yet Easy-to-Use
• Designed for Both Experts and Novices
• Automated Synchronizations and Backups
• Increases Your Flexibility and Productivity
• Decreases Risk of Important Data Loss
• Recommended by Experts and Users Alike