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.
mFax - mFax is a cloud-based fax solution for sending and receiving faxes from any device.
Dropbox - Online Sync and File Sharing
Hellofax - Easy. Reliable. Online faxing. Send & receive faxes from anywhere.
Google Drive - Access and sync your files anywhere
eFax - Over 11 million people use eFax every day for their fax communications.
Mega - Secure File Storage and collaboration