For hosting common files it's ok. Also it is on Android too do, great to transfer files between your Windows and your phone. But if you want better security you have to subscribe a monthly offer.
Communifire - Enterprise Social Collaboration Software
Dropbox - Online Sync and File Sharing
LS Intranet - LS Intranet is a corporate intranet that facilitates multiple employees collaborating on projects, and working in synergy.
Google Drive - Access and sync your files anywhere
Unily - Unily is a cloud-based intranet solution designed by SharePoint consultancy BrightStarr.
Mega - Secure File Storage and collaboration