Syncplicity offers 10 GB for free.
Some features of the free version of Syncplicity:
- Unlimited file size sync
- Unlimited number of devices
- Zero bandwidth restrictions
- Sync any desktop folder
- Real-Time document versioning and backup
- Secure mobile editing and PDF annotation
- Universal access to all content from any device
- Share files and collaborate with anyone
- Send any size file / folders with add-in for Outlook
- Choice of public cloud storage location (US or EU)
- Mobile Office editing and PDF annotation
Source: Syncplicity